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Sample records for cornea syndrome locus

  1. Common genetic variants near the Brittle Cornea Syndrome locus ZNF469 influence the blinding disease risk factor central corneal thickness.

    Directory of Open Access Journals (Sweden)

    Yi Lu

    2010-05-01

    Full Text Available Central corneal thickness (CCT, one of the most highly heritable human traits (h(2 typically>0.9, is important for the diagnosis of glaucoma and a potential risk factor for glaucoma susceptibility. We conducted genome-wide association studies in five cohorts from Australia and the United Kingdom (total N = 5058. Three cohorts were based on individually genotyped twin collections, with the remaining two cohorts genotyped on pooled samples from singletons with extreme trait values. The pooled sample findings were validated by individual genotyping the pooled samples together with additional samples also within extreme quantiles. We describe methods for efficient combined analysis of the results from these different study designs. We have identified and replicated quantitative trait loci on chromosomes 13 and 16 for association with CCT. The locus on chromosome 13 (nearest gene FOXO1 had an overall meta-analysis p-value for all the individually genotyped samples of 4.6x10(-10. The locus on chromosome 16 was associated with CCT with p = 8.95x10(-11. The nearest gene to the associated chromosome 16 SNPs was ZNF469, a locus recently implicated in Brittle Cornea Syndrome (BCS, a very rare disorder characterized by abnormal thin corneas. Our findings suggest that in addition to rare variants in ZNF469 underlying CCT variation in BCS patients, more common variants near this gene may contribute to CCT variation in the general population.

  2. Brittle Cornea Syndrome Associated with a Missense Mutation in the Zinc-Finger 469 Gene

    DEFF Research Database (Denmark)

    Christensen, Anne Elisabeth; Knappskog, Per Morten; Midtbø, Marit

    2010-01-01

    Purpose: To investigate the diverse clinical manifestations, identify the causative mutation and explain the association with red hair in a family with brittle cornea syndrome (BCS). Methods: Eight family members in three generations underwent ophthalmic, dental, and general medical examination...... mapping with SNP markers, DNA sequencing, and MC1R genotyping. Results: At 42 and 48 years of age, respectively, both affected individuals were blind due to retinal detachment and secondary glaucoma. They had extremely thin and bulging corneas, velvety skin, chestnut colored hair, scoliosis, reduced BMD......, dental anomalies, hearing loss and minor cardiac defects. The morphologies of the skin biopsies were normal except that in some areas slightly thinner collagen fibrils were seen in one of the affected individuals. Molecular genetic analysis revealed a novel missense mutation of ZNF469, c.10016G...

  3. Refined localization of the Prieto-syndrome locus

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    Martinez, F.; Prieto, F. [Unidad de Genetica, Valencia (Spain); Gal, A. [Universitaets-Krankenhaus Eppendorf, Hamburg (Germany)

    1996-07-12

    PRS designates the locus for a syndromal form of X-linked mental retardation (Prieto syndrome) characterized by minor facial anomalies, ear malformation, abnormal growth of teeth, clinodactyly, sacral dimple, patellar luxation, malformation of lower limbs, abnormalities of the fundus of the eye, and subcortical cerebral atrophy. Linkage analysis localized the disease locus between DXS84 (Xp21.1) and DXS255. Here we present additional linkage data that provide further support and refinement of this localization. Individual III-18 gave birth to a male, currently aged 2 7/12 years, who clearly shows delayed psychomotor development. He began to walk at 23 months and his speech is delayed. In addition, he shows the characteristic facial anomalies, {open_quotes}dysplastic{close_quotes} ears, sacral dimple, and clinodactyly, as do all other affected males in this family. 7 refs., 1 tab.

  4. [Locus of control in girls with anorexia readiness syndrome].

    Science.gov (United States)

    Jaros, Katarzyna; Oszwa, Urszula

    2014-01-01

    The aim of the research was to indicate whether there are differences between locus of control (LOC) in girls with anorexia readiness syndrome (ARS) and without this syndrome. There was also a question about the relationship between LOC and the tendency to respond in incorrect attitudes towards food, eating and their bodies under stress. The sample consisted of girls aged 13-18 years randomly selected from five public Polish middle and high schools. Tools: 1) Eating Attitudes Questionnaire (EAQ) by B. Ziółkowska; 2) Locus of Control Questionnaire (LOCQ) by G. Krasowicz, A. Kurzyp-Wojnarska, to assess LOC of the subjects. The criterion group (N=23) was formed by girls who received high score in EAQ (signs of ARS) in the first stage of research (N=189). The control group (N = 23) were girls who received a low score in EAQ (no signs of ARS). Subjects with ARS were characterized by more external LOC than girls without any signs of this syndrome (t = -2.898; p control, LOC may play a role as a mediating variable rather than a direct determinant of this syndrome.

  5. A large duplication involving the IHH locus mimics acrocallosal syndrome.

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    Yuksel-Apak, Memnune; Bögershausen, Nina; Pawlik, Barbara; Li, Yun; Apak, Selcuk; Uyguner, Oya; Milz, Esther; Nürnberg, Gudrun; Karaman, Birsen; Gülgören, Ayan; Grzeschik, Karl-Heinz; Nürnberg, Peter; Kayserili, Hülya; Wollnik, Bernd

    2012-06-01

    Indian hedgehog (Ihh) signaling is a major determinant of various processes during embryonic development and has a pivotal role in embryonic skeletal development. A specific spatial and temporal expression of Ihh within the developing limb buds is essential for accurate digit outgrowth and correct digit number. Although missense mutations in IHH cause brachydactyly type A1, small tandem duplications involving the IHH locus have recently been described in patients with mild syndactyly and craniosynostosis. In contrast, a ∼600-kb deletion 5' of IHH in the doublefoot mouse mutant (Dbf) leads to severe polydactyly without craniosynostosis, but with craniofacial dysmorphism. We now present a patient resembling acrocallosal syndrome (ACS) with extensive polysyndactyly of the hands and feet, craniofacial abnormalities including macrocephaly, agenesis of the corpus callosum, dysplastic and low-set ears, severe hypertelorism and profound psychomotor delay. Single-nucleotide polymorphism (SNP) array copy number analysis identified a ∼900-kb duplication of the IHH locus, which was confirmed by an independent quantitative method. A fetus from a second pregnancy of the mother by a different spouse showed similar craniofacial and limb malformations and the same duplication of the IHH-locus. We defined the exact breakpoints and showed that the duplications are identical tandem duplications in both sibs. No copy number changes were observed in the healthy mother. To our knowledge, this is the first report of a human phenotype similar to the Dbf mutant and strikingly overlapping with ACS that is caused by a copy number variation involving the IHH locus on chromosome 2q35.

  6. A role for repressive complexes and H3K9 di-methylation in PRDM5-associated brittle cornea syndrome

    DEFF Research Database (Denmark)

    Porter, Louise F; Galli, Giorgio G; Williamson, Sally

    2015-01-01

    skin fibroblasts and retinal tissue from BCS2 patients, to elucidate the epigenetic role of PRDM5 and mechanisms of its dysregulation in disease.First we report abnormal retinal vascular morphology in the eyes of two cousins with BCS2 (PRDM5 Δ exons 9-14) using immunohistochemistry, and mine data from......, and dysregulated H3K9 di-methylation in skin fibroblasts of three patients (p.Arg590*, p.Glu134* and Δ exons 9-14) by western blotting. These findings suggest that defective interaction of PRDM5 with repressive complexes, and dysregulation of H3K9 di-methylation, play a role in PRDM5-associated disease.......Type 2 brittle cornea syndrome (BCS2) is an inherited connective tissue disease with a devastating ocular phenotype caused by mutations in the transcription factor PRDM5 hypothesised to exert epigenetic effects through histone and DNA methylation. Here we investigate clinical samples, including...

  7. Identification of a novel locus for a USH3 like syndrome combined with congenital cataract.

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    Dad, S; Østergaard, E; Thykjaer, T; Albrectsen, A; Ravn, K; Rosenberg, T; Møller, L B

    2010-10-01

    Usher syndrome (USH) is the most common genetic disease that causes both deafness and blindness. USH is divided into three types, USH1, USH2 and USH3, depending on the age of onset, the course of the disease, and on the degree of vestibular dysfunction. By homozygosity mapping of a consanguineous Danish family of Dutch descent, we have identified a novel locus for a rare USH3-like syndrome. The affected family members have a unique association of retinitis pigmentosa, progressive hearing impairment, vestibular dysfunction, and congenital cataract. The phenotype is similar, but not identical to that of USH3 patients, as congenital cataract has not been reported for USH3. By homozygosity mapping, we identified a 7.3 Mb locus on chromosome 15q22.2-23 with a maximum multipoint LOD score of 2.0. The locus partially overlaps with the USH1 locus, USH1H, a novel unnamed USH2 locus, and the non-syndromic deafness locus DFNB48. © 2010 John Wiley & Sons A/S.

  8. Identification of a novel locus for a USH3 like syndrome combined with congenital cataract

    DEFF Research Database (Denmark)

    Dad, S.; Østergaard, Elsebet; Thykjær, T.

    2010-01-01

    Usher syndrome (USH) is the most common genetic disease that causes both deafness and blindness. USH is divided into three types, USH1, USH2 and USH3, depending on the age of onset, the course of the disease, and on the degree of vestibular dysfunction. By homozygosity mapping of a consanguineous...... Danish family of Dutch descent, we have identified a novel locus for a rare USH3-like syndrome. The affected family members have a unique association of retinitis pigmentosa, progressive hearing impairment, vestibular dysfunction, and congenital cataract. The phenotype is similar, but not identical...... to that of USH3 patients, as congenital cataract has not been reported for USH3. By homozygosity mapping, we identified a 7.3 Mb locus on chromosome 15q22.2-23 with a maximum multipoint LOD score of 2.0. The locus partially overlaps with the USH1 locus, USH1H, a novel unnamed USH2 locus, and the non-syndromic...

  9. Immotile cilia syndrome: A recombinant family at HLA-linked gene locus

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    Gasparini, P.; Grifa, A.; Oggiano, N.; Fabbrizzi, E.; Giorgi, P.L. [Univsita di Ancona (Israel)

    1994-02-15

    The immotile-cilia syndrome (ICS) is an autosomal recessive trait of congenital dismobility or even complete immobility of cilia in the ciliated epithelia (MIM 244400). Recurrent upper respiratory infections in early childhood are the most common clinical findings. Recently a disease locus was mapped by sib pair analysis in two unrelated families on 6p tightly linked to HLA class II loci, such as DR and DQ. In order to confirm this assignment and to test the presence of possible heterogeneity, the authors analyzed several ICS families utilizing DNA makers of HLA class II region. Here they report the identification of a recombinant family at this locus. 3 refs., 1 fig.

  10. Refinement of the locus for non-syndromic sensorineural deafness ...

    Indian Academy of Sciences (India)

    Unknown

    2004-04-05

    Apr 5, 2004 ... GANG PEI 1,2 , XIANGYIN KONG 1 and LANDIAN HU 1 *. 1Health Science Center ... ever, a further study of the same family revealed that deafness was ... ment with ototoxic drugs, or ear infections, was excluded. There was no .... ness syndrome with blindness, dystonia, fractures, and mental deficiency is ...

  11. Effects of amino acids enriched tears substitutes on the cornea of patients with dysfunctional tear syndrome.

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    Aragona, Pasquale; Rania, Laura; Roszkowska, Anna M; Spinella, Rosaria; Postorino, Elisa; Puzzolo, Domenico; Micali, Antonio

    2013-09-01

    To evaluate the effect of aminoacid enriched artificial tears on the ocular surface of patients with dysfunctional tear syndrome (DTS). Forty patients were divided into two groups: group 1 treated for 90 days with sodium hyaluronate (SH) 0.15% 1 drop × 5 times/day; group 2 treated for 90 days with SH 0.15% + aminoacids mixture 1 drop × 5 times/day. Symptom score questionnaire, tear break-up time (TBUT), corneal fluorescein stain, Shirmer's I test and confocal microscopy were performed at baseline and after 30 and 90 days. Confocal images underwent morphometric analysis. Both treatments improved symptoms after 1 month. Group 2 patients showed at 1 month an improvement of TBUT and corneal stain, maintained throughout the study. Also Shirmer's I test improved after 3 months. In group 1, an improvement of TBUT and corneal stain was observed after 3 months. The morphometric analysis of confocal images demonstrated at month 1 an improvement of nerve tortuosity in group 2; after 3 months both groups showed a significant improvement versus baseline. The epithelium showed, in both groups, a reduction in hyperreflective large cells starting from 1 month; the area of the cells was significantly reduced after 3 months, with a significant higher reduction in group 2. The perineural stromal opacity was significantly increased after 3 months, particularly in group 2. This is the first study addressing corneal changes after amino acids administration in a DTS population. The treatment with amino acids enriched SH can be considered a useful tool in the treatment of DTS. © 2013 The Authors Acta Ophthalmologica © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by Blackwell Publishing Ltd.

  12. Locus heterogeneity for Waardenburg syndrome is predictive of clinical subtypes.

    Science.gov (United States)

    Farrer, L A; Arnos, K S; Asher, J H; Baldwin, C T; Diehl, S R; Friedman, T B; Greenberg, J; Grundfast, K M; Hoth, C; Lalwani, A K

    1994-10-01

    Waardenburg syndrome (WS) is a dominantly inherited and clinically variable syndrome of deafness, pigmentary changes, and distinctive facial features. Clinically, WS type I (WS1) is differentiated from WS type II (WS2) by the high frequency of dystopia canthorum in the family. In some families, WS is caused by mutations in the PAX3 gene on chromosome 2q. We have typed microsatellite markers within and flanking PAX3 in 41 WS1 kindreds and 26 WS2 kindreds in order to estimate the proportion of families with probable mutations in PAX3 and to study the relationship between phenotypic and genotypic heterogeneity. Evaluation of heterogeneity in location scores obtained by multilocus analysis indicated that WS is linked to PAX3 in 60% of all WS families and in 100% of WS1 families. None of the WS2 families were linked. In those families in which equivocal lod scores (between -2 and +1) were found, PAX3 mutations have been identified in 5 of the 15 WS1 families but in none of the 4 WS2 families. Although preliminary studies do not suggest any association between the phenotype and the molecular pathology in 20 families with known PAX3 mutations and in four patients with chromosomal abnormalities in the vicinity of PAX3, the presence of dystopia in multiple family members is a reliable indicator for identifying families likely to have a defect in PAX3.

  13. Transcription is required to establish maternal imprinting at the Prader-Willi syndrome and Angelman syndrome locus.

    Directory of Open Access Journals (Sweden)

    Emily Y Smith

    2011-12-01

    Full Text Available The Prader-Willi syndrome (PWS [MIM 17620] and Angelman syndrome (AS [MIM 105830] locus is controlled by a bipartite imprinting center (IC consisting of the PWS-IC and the AS-IC. The most widely accepted model of IC function proposes that the PWS-IC activates gene expression from the paternal allele, while the AS-IC acts to epigenetically inactivate the PWS-IC on the maternal allele, thus silencing the paternally expressed genes. Gene order and imprinting patterns at the PWS/AS locus are well conserved from human to mouse; however, a murine AS-IC has yet to be identified. We investigated a potential regulatory role for transcription from the Snrpn alternative upstream exons in silencing the maternal allele using a murine transgene containing Snrpn and three upstream exons. This transgene displayed appropriate imprinted expression and epigenetic marks, demonstrating the presence of a functional AS-IC. Transcription of the upstream exons from the endogenous locus correlates with imprint establishment in oocytes, and this upstream exon expression pattern was conserved on the transgene. A transgene bearing targeted deletions of each of the three upstream exons exhibited loss of imprinting upon maternal transmission. These results support a model in which transcription from the Snrpn upstream exons directs the maternal imprint at the PWS-IC.

  14. USH1H, a novel locus for type I Usher syndrome, maps to chromosome 15q22-23.

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    Ahmed, Z M; Riazuddin, S; Khan, S N; Friedman, P L; Riazuddin, S; Friedman, T B

    2009-01-01

    Usher syndrome (USH) is a hereditary disorder associated with sensorineural hearing impairment, progressive loss of vision attributable to retinitis pigmentosa (RP) and variable vestibular function. Three clinical types have been described with type I (USH1) being the most severe. To date, six USH1 loci have been reported. We ascertained two large Pakistani consanguineous families segregating profound hearing loss, vestibular dysfunction, and RP, the defining features of USH1. In these families, we excluded linkage of USH to the 11 known USH loci and subsequently performed a genome-wide linkage screen. We found a novel USH1 locus designated USH1H that mapped to chromosome 15q22-23 in a 4.92-cM interval. This locus overlaps the non-syndromic deafness locus DFNB48 raising the possibility that the two disorders may be caused by allelic mutations.

  15. Identification of candidate regions for a novel Usher syndrome type II locus.

    Science.gov (United States)

    Ben Rebeh, Imen; Benzina, Zeineb; Dhouib, Houria; Hadjamor, Imen; Amyere, Mustapha; Ayadi, Leila; Turki, Khalil; Hammami, Bouthaina; Kmiha, Noureddine; Kammoun, Hassen; Hakim, Bochra; Charfedine, Ilhem; Vikkula, Miikka; Ghorbel, Abdelmonem; Ayadi, Hammadi; Masmoudi, Saber

    2008-09-19

    Chronic diseases affecting the inner ear and the retina cause severe impairments to our communication systems. In more than half of the cases, Usher syndrome (USH) is the origin of these double defects. Patients with USH type II (USH2) have retinitis pigmentosa (RP) that develops during puberty, moderate to severe hearing impairment with downsloping pure-tone audiogram, and normal vestibular function. Four loci and three genes are known for USH2. In this study, we proposed to localize the gene responsible for USH2 in a consanguineous family of Tunisian origin. Affected members underwent detailed ocular and audiologic characterization. One Tunisian family with USH2 and 45 healthy controls unrelated to the family were recruited. Two affected and six unaffected family members attended our study. DNA samples of eight family members were genotyped with polymorphic markers. Two-point and multipoint LOD scores were calculated using Genehunter software v2.1. Sequencing was used to investigate candidate genes. Haplotype analysis showed no significant linkage to any known USH gene or locus. A genome-wide screen, using microsatellite markers, was performed, allowing the identification of three homozygous regions in chromosomes 2, 4, and 15. We further confirmed and refined these three regions using microsatellite and single-nucleotide polymorphisms. With recessive mode of inheritance, the highest multipoint LOD score of 1.765 was identified for the candidate regions on chromosomes 4 and 15. The chromosome 15 locus is large (55 Mb), underscoring the limited number of meioses in the consanguineous pedigree. Moreover, the linked, homozygous chromosome 15q alleles, unlike those of the chromosome 2 and 4 loci, are infrequent in the local population. Thus, the data strongly suggest that the novel locus for USH2 is likely to reside on 15q. Our data provide a basis for the localization and the identification of a novel gene implicated in USH2, most likely localized on 15q.

  16. Cytogenetic mapping of a novel locus for type II Waardenburg syndrome.

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    Selicorni, Angelo; Guerneri, Silvana; Ratti, Antonia; Pizzuti, Antonio

    2002-01-01

    An Italian family in which Waardenburg syndrome type II (WS2) segregates together with a der(8) chromosome from a (4p;8p) balanced translocation was studied. Cytogenetic analysis by painting and subtelomeric probe hybridization positioned the chromosome 8 breakpoint at p22-pter. Fluorescence in situ hybridization analysis with yeast artificial chromosomes from a contig spanning the 8p21-pter region refined the breakpoint in an interval of less than 170 kb between markers WI-3823 and D8S1819. The only cloned gene for WS2 is that for microphtalmia (MITF) on chromosome 3p. In this family, MITF mutations were excluded by sequencing the whole coding region. The 8p23 region may represent a third locus for WS2 (WS2C).

  17. The Drosophila agnostic Locus: Involvement in the Formation of Cognitive Defects in Williams Syndrome.

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    Nikitina, E A; Medvedeva, A V; Zakharov, G A; Savvateeva-Popova, E V

    2014-04-01

    The molecular basis of the pathological processes that lead to genome disorders is similar both in invertebrates and mammals. Since cognitive impairments in Williams syndrome are caused by LIMK1 hemizygosity, could the spontaneous and mutant variants of the Drosophila limk1 gene serve as a model for studying two diagnostic features from three distinct cognitive defects of the syndrome? These two symptoms are the disturbance of visuospatial orientation and an unusualy strong fixation on the faces of other people during pairwise interaction with a stranger. An experimental approach to the first cognitive manifestation might be an analysis of the locomotor behavior of Drosophila larvae involving visuospatial orientation during the exploration of the surrounding environment. An approach to tackle the second manifestation might be an analysis of the most natural ways of contact between a male and a female during courtship (the first stage of this ritual is the orientation of a male towards a female and following the female with constant fixation on the female's image). The present study of locomotor activity and cognitive repertoire in spontaneous and mutant variants of the Drosophila agnostic locus allows one to bridge alterations in the structure of the limk1 gene and behavior.

  18. Refinement of the X-linked cataract locus (CXN) and gene analysis for CXN and Nance-Horan syndrome (NHS).

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    Brooks, Simon; Ebenezer, Neil; Poopalasundaram, Subathra; Maher, Eamonn; Francis, Peter; Moore, Anthony; Hardcastle, Alison

    2004-06-01

    The X-linked congenital cataract (CXN) locus has been mapped to a 3-cM (approximately 3.5 Mb) interval on chromosome Xp22.13, which is syntenic to the mouse cataract disease locus Xcat and encompasses the recently refined Nance-Horan syndrome (NHS) locus. A positional cloning strategy has been adopted to identify the causative gene. In an attempt to refine the CXN locus, seven microsatellites were analysed within 21 individuals of a CXN family. Haplotypes were reconstructed confirming disease segregation with markers on Xp22.13. In addition, a proximal cross-over was observed between markers S3 and S4, thereby refining the CXN disease interval by approximately 400 Kb to 3.2 Mb, flanked by markers DXS9902 and S4. Two known genes (RAI2 and RBBP7) and a novel gene (TL1) were screened for mutations within an affected male from the CXN family and an NHS family by direct sequencing of coding exons and intron- exon splice sites. No mutations or polymorphisms were identified, therefore excluding them as disease-causative in CXN and NHS. In conclusion, the CXN locus has been successfully refined and excludes PPEF1 as a candidate gene. A further three candidates were excluded based on sequence analysis. Future positional cloning efforts will focus on the region of overlap between CXN, Xcat, and NHS.

  19. Patients suffering from restless legs syndrome have low internal locus of control and poor psychological functioning compared to healthy controls.

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    Brand, Serge; Beck, Johannes; Hatzinger, Martin; Holsboer-Trachsler, Edith

    2013-01-01

    Restless legs syndrome (RLS) is a disturbing sensorimotor disorder negatively influencing both sleep and psychological functioning. The aim of the present study was to assess RLS patients with respect to locus of control, sleep-related personality traits, quality of life, and sleep as compared to healthy controls. Thirty-eight patients (18 females and 20 males; mean age: 56.06 years) diagnosed with RLS and an age- and gender-matched control group (n = 42) were recruited. Participants completed a series of questionnaires related to locus of control, personality traits, quality of life, and sleep. Compared to healthy controls, RLS patients had a lower internal locus of control, unfavourable sleep-related personality traits such as low self-confidence and higher mental arousal, poorer quality of life, and more depressive symptoms. Sleep was also affected. Multiple regression analyses showed that a low internal and a high external locus of control were predicted by RLS. The pattern of results suggests that RLS is associated with a low locus of control, negative personality traits, and poor quality of life as compared to healthy controls. Copyright © 2013 S. Karger AG, Basel.

  20. CORNEA AND ANTERIOR SEGMENT

    African Journals Online (AJOL)

    Yet, fewer than 150,000 corneal transplant surgeries are performed annually worldwide. Corneal blindness arises from a wide variety of causes, from mechanical, chemical, and radiation injury to microbial infections and corneal degenerative diseases. The use of human cadaver donor corneas has been limited by its often.

  1. A novel locus for Usher syndrome type I, USH1G, maps to chromosome 17q24-25.

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    Mustapha, Mirna; Chouery, Eliane; Torchard-Pagnez, Delphine; Nouaille, Sylvie; Khrais, Awni; Sayegh, Fouad N; Mégarbané, André; Loiselet, Jacques; Lathrop, Mark; Petit, Christine; Weil, Dominique

    2002-04-01

    Usher syndrome (USH) is an autosomal recessive disorder associated with sensorineural hearing impairment and progressive visual loss attributable to retinitis pigmentosa. This syndrome is both clinically and genetically heterogeneous. Three clinical types have been described of which type I (USH1) is the most severe. Six USH1 loci have been identified. We report a Palestinian consanguineous family from Jordan with three affected children. In view of the combination of profound hearing loss, vestibular dysfunction, and retinitis pigmentosa in the patients, we classified the disease as USH1. Linkage analysis excluded the involvement of any of the known USH1 loci. A genome-wide screening allowed us to map this novel locus, USH1G, in a 23-cM interval on chromosome 17q24-25. The USH1G interval overlaps the intervals for two dominant forms of isolated hearing loss, namely DFNA20 and DFNA26. Since several examples have been reported of syndromic and isolated forms of deafness being allelic, USH1G, DFNA20, and DFNA26 might result from alterations of the same gene. Finally, a mouse mutant, jackson shaker ( js), with deafness and circling behavior has been mapped to the murine homologous region on chromosome 11.

  2. Stress, Locus of Control, and Family Cohesion and Adaptability in Parents of Children with Down, Williams, Fragile X, and Prader-Willi Syndromes

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    Lanfranchi, Silvia; Vianello, Renzo

    2012-01-01

    The present study analyzes differences in parental stress in families of children with Down, Williams, Fragile X, and Prader-Willi syndromes, exploring factors that influence parental stress, such as child's characteristics, parental locus of control, and family cohesion and adaptability. Differences between mothers and fathers are also…

  3. Linkage analysis in a family with Stickler syndrome leads to the exclusion of the COL2A1 locus

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    Mottes, M.; Zolezzi, F.; Pignatti, P.F. [Univ. of Verona (Italy)

    1994-09-01

    Hereditary arthro-ophtalmopathy (AO) or Stickler Syndrome (MIM No. 10830) is a dominantly inherited disorder characterized by vitro-retinal degeneration and other connective tissue disturbances. Mutations in the COL2A1 gene, coding for type II collagen chains, have been described in a few patients. The wide spectrum of clinical manifestations is presumably due to genetic heterogeneity, since only about 50% of the Stickler families so far studied show cosegregation of the disease with the COL2A1 locus. We have investigated a large pedigree (19 individuals of whom 9 are affected) in which severe myopia with vitro-retinal degeneration consegregated with joint laxity, recurrent inguinal hernias, and degenerative changes of the hip and the knee. The 3{prime} end COL2A1 VNTR polymorphism was utilized for linkage analysis. In order to get the maximum informativity, we have analyzed the allelic microheterogeneity of this VNTR, due to the repeat sequence variation, by means of a single strand polymorphism. Mendelian inheritance of the different single strands was observed as expected. Discordance of segregation between the disease and the COL2A1 locus was thus established inequivocally in this family.

  4. Clinical variability of Waardenburg-Shah syndrome in patients with proximal 13q deletion syndrome including the endothelin-B receptor locus.

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    Tüysüz, Beyhan; Collin, Anna; Arapoğlu, Müjde; Suyugül, Nezir

    2009-10-01

    Waardenburg-Shah syndrome (Waardenburg syndrome type IV-WS4) is an auditory-pigmentary disorder that combines clinical features of pigmentary abnormalities of the skin, hair and irides, sensorineural hearing loss, and Hirschsprung disease (HSCR). Mutations in the endothelin-B receptor (EDNRB) gene on 13q22 have been found to cause this syndrome. Mutations in both alleles cause the full phenotype, while heterozygous mutations cause isolated HSCR or HSCR with minor pigmentary anomalies and/or sensorineural deafness. We investigated the status of the EDNRB gene, by FISH analysis, in three patients with de novo proximal 13q deletions detected at cytogenetic analysis and examined the clinical variability of WS4 among these patients. Chromosome 13q was screened with locus specific FISH probes and breakpoints were determined at 13q22.1q31.3 in Patients 1 and 3, and at 13q21.1q31.3 in Patient 2. An EDNRB specific FISH probe was deleted in all three patients. All patients had common facial features seen in proximal 13q deletion syndrome and mild mental retardation. However, findings related to WS4 were variable; Patient 1 had hypopigmentation of the irides and HSCR, Patient 2 had prominent bicolored irides and mild bilateral hearing loss, and Patient 3 had only mild unilateral hearing loss. These data contribute new insights into the pathogenesis of WS4.

  5. High-resolution physical map for chromosome 16q12.1-q13, the Blau syndrome locus

    Directory of Open Access Journals (Sweden)

    Bonavita Gina

    2002-08-01

    Full Text Available Abstract Background The Blau syndrome (MIM 186580, an autosomal dominant granulomatous disease, was previously mapped to chromosome 16p12-q21. However, inconsistent physical maps of the region and consequently an unknown order of microsatellite markers, hampered us from further refining the genetic locus for the Blau syndrome. To address this problem, we constructed our own high-resolution physical map for the Blau susceptibility region. Results We generated a high-resolution physical map that provides more than 90% coverage of a refined Blau susceptibility region. The map consists of four contigs of sequence tagged site-based bacterial artificial chromosomes with a total of 124 bacterial artificial chromosomes, and spans approximately 7.5 Mbp; however, three gaps still exist in this map with sizes of 425, 530 and 375 kbp, respectively, estimated from radiation hybrid mapping. Conclusions Our high-resolution map will assist genetic studies of loci in the interval from D16S3080, near D16S409, and D16S408 (16q12.1 to 16q13.

  6. Exome analysis of a family with Wolff-Parkinson-White syndrome identifies a novel disease locus.

    Science.gov (United States)

    Bowles, Neil E; Jou, Chuanchau J; Arrington, Cammon B; Kennedy, Brett J; Earl, Aubree; Matsunami, Norisada; Meyers, Lindsay L; Etheridge, Susan P; Saarel, Elizabeth V; Bleyl, Steven B; Yost, H Joseph; Yandell, Mark; Leppert, Mark F; Tristani-Firouzi, Martin; Gruber, Peter J

    2015-12-01

    Wolff-Parkinson-White (WPW) syndrome is a common cause of supraventricular tachycardia that carries a risk of sudden cardiac death. To date, mutations in only one gene, PRKAG2, which encodes the 5'-AMP-activated protein kinase subunit γ-2, have been identified as causative for WPW. DNA samples from five members of a family with WPW were analyzed by exome sequencing. We applied recently designed prioritization strategies (VAAST/pedigree VAAST) coupled with an ontology-based algorithm (Phevor) that reduced the number of potentially damaging variants to 10: a variant in KCNE2 previously associated with Long QT syndrome was also identified. Of these 11 variants, only MYH6 p.E1885K segregated with the WPW phenotype in all affected individuals and was absent in 10 unaffected family members. This variant was predicted to be damaging by in silico methods and is not present in the 1,000 genome and NHLBI exome sequencing project databases. Screening of a replication cohort of 47 unrelated WPW patients did not identify other likely causative variants in PRKAG2 or MYH6. MYH6 variants have been identified in patients with atrial septal defects, cardiomyopathies, and sick sinus syndrome. Our data highlight the pleiotropic nature of phenotypes associated with defects in this gene. © 2015 Wiley Periodicals, Inc.

  7. Exome Analysis of a Family with Wolff–Parkinson–White Syndrome Identifies a Novel Disease Locus

    Science.gov (United States)

    Bowles, Neil E.; Jou, Chuanchau J.; Arrington, Cammon B.; Kennedy, Brett J.; Earl, Aubree; Matsunami, Norisada; Meyers, Lindsay L.; Etheridge, Susan P.; Saarel, Elizabeth V.; Bleyl, Steven B.; Yost, H. Joseph; Yandell, Mark; Leppert, Mark F.; Tristani-Firouzi, Martin; Gruber, Peter J.

    2016-01-01

    Wolff–Parkinson–White (WPW) syndrome is a common cause of supraventricular tachycardia that carries a risk of sudden cardiac death. To date, mutations in only one gene, PRKAG2, which encodes the 5’ -AMP-activated protein kinase subunit γ-2, have been identified as causative for WPW. DNA samples from five members of a family with WPW were analyzed by exome sequencing. We applied recently designed prioritization strategies (VAAST/pedigree VAAST) coupled with an ontology-based algorithm (Phevor) that reduced the number of potentially damaging variants to 10: a variant in KCNE2 previously associated with Long QT syndrome was also identified. Of these 11 variants, only MYH6 p.E1885K segregated with the WPW phenotype in all affected individuals and was absent in 10 unaffected family members. This variant was predicted to be damaging by in silico methods and is not present in the 1,000 genome and NHLBI exome sequencing project databases. Screening of a replication cohort of 47 unrelated WPW patients did not identify other likely causative variants in PRKAG2 or MYH6. MYH6 variants have been identified in patients with atrial septal defects, cardiomyopathies, and sick sinus syndrome. Our data highlight the pleiotropic nature of phenotypes associated with defects in this gene. PMID:26284702

  8. Mapping recessive ophthalmic diseases: linkage of the locus for Usher syndrome type II to a DNA marker on chromosome 1q.

    Science.gov (United States)

    Lewis, R A; Otterud, B; Stauffer, D; Lalouel, J M; Leppert, M

    1990-06-01

    Usher syndrome is a heterogeneous group of autosomal recessive disorders that combines variably severe congenital neurosensory hearing impairment with progressive night-blindness and visual loss similar to that in retinitis pigmentosa. Usher syndrome type I is distinguished by profound congenital (preverbal) deafness and retinal disease with onset in the first decade of life. Usher syndrome type II is characterized by partial hearing impairment and retinal dystrophy that occurs in late adolescence or early adulthood. The chromosomal assignment and the regional localization of the genetic mutation(s) causing the Usher syndromes are unknown. We analyzed a panel of polymorphic genomic markers for linkage to the disease gene among six families with Usher syndrome type I and 22 families with Usher syndrome type II. Significant linkage was established between Usher syndrome type II and the DNA marker locus THH33 (D1S81), which maps to chromosome 1q. The most likely location of the disease gene is at a map distance of 9 cM from THH33 (lod score 6.5). The same marker failed to show linkage in families segregating an allele for Usher syndrome type I. These data confirm the provisional assignment of the locus for Usher syndrome type II to the distal end of chromosome 1q and demonstrate that the clinical heterogeneity between Usher types I and II is caused by mutational events at different genetic loci. Regional localization has the potential to improve carrier detection and to provide antenatal diagnosis in families at risk for the disease.

  9. Churg-Strauss syndrome presenting as scar reactivation: histopathologic features and an illustration of 'locus minoris resistentiae'.

    Science.gov (United States)

    Gee, Sarah N; Harris, Anna C; Zimarowski, Mary Jane

    2013-05-01

    We report a 33-year-old female with cutaneous involvement by Churg-Strauss syndrome confined to surgical scars that were obtained 13 years before. She presented to the emergency department with 2-day history of fever, night sweats, right-sided weakness, hoarseness and worsening asthma symptoms. She was found to have an eosinophilia and two sub-5-mm pulmonary nodules. The patient also reported that the scars on her right thumb, inner wrist and back had been swollen, red and painful for 2 days. Examination revealed tender, erythematous, well-healed edematous scars studded with small skin colored papules. She had no clinical findings that were classic for cutaneous vasculitis. A skin biopsy of a scar revealed perivascular and palisading granulomatous inflammation consisting of histiocytes and neutrophils with leukocytoclasia. Focal vascular injury was identified. Scattered tissue eosinophils were seen. Special stains were negative for infection. Thereafter, she was started on intravenous steroids, at which point the fever, pulmonary and cutaneous symptoms subsided. Although scar sarcoidosis is a well-described phenomenon, granulomatous inflammation and vasculitis seen in Churg-Strauss syndrome exclusively manifesting in well-healed surgical scars highlights the unique features seen in this case and draws attention to the concept of locus minoris resistentiae. This case also highlights how a skin biopsy in the setting of suspected systemic vasculitis can confirm the presence of vasculitis and/or granulomatous inflammation and obviate the need for more invasive, higher risk procedures such as lung biopsy. Copyright © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  10. Autozygosity mapping of a large consanguineous Pakistani family reveals a novel non-syndromic autosomal recessive mental retardation locus on 11p15-tel

    DEFF Research Database (Denmark)

    Rehman, Shoaib ur; Baig, Shahid Mahmood; Eiberg, Hans

    2011-01-01

    done in all sampled individuals in the family. The nuclear central loop in the five generation family showed homozygosity for a 6-Mb telomeric region on 11p15, whereas all other linkage regions were excluded by calculation of logarithm of odds (LOD) for the SNP microarray data. A maximum LOD score of Z......Autosomal recessive inherited mental retardation is an extremely heterogeneous disease and accounts for approximately 25% of all non-syndromic mental retardation cases. Autozygosity mapping of a large consanguineous Pakistani family revealed a novel locus for non-syndromic autosomal recessive...

  11. Deletions at the SOX10 gene locus cause Waardenburg syndrome types 2 and 4.

    Science.gov (United States)

    Bondurand, Nadege; Dastot-Le Moal, Florence; Stanchina, Laure; Collot, Nathalie; Baral, Viviane; Marlin, Sandrine; Attie-Bitach, Tania; Giurgea, Irina; Skopinski, Laurent; Reardon, William; Toutain, Annick; Sarda, Pierre; Echaieb, Anis; Lackmy-Port-Lis, Marilyn; Touraine, Renaud; Amiel, Jeanne; Goossens, Michel; Pingault, Veronique

    2007-12-01

    Waardenburg syndrome (WS) is an auditory-pigmentary disorder that exhibits varying combinations of sensorineural hearing loss and abnormal pigmentation of the hair and skin. Depending on additional symptoms, WS is classified into four subtypes, WS1-WS4. Absence of additional features characterizes WS2. The association of facial dysmorphic features defines WS1 and WS3, whereas the association with Hirschsprung disease (aganglionic megacolon) characterizes WS4, also called "Waardenburg-Hirschsprung disease." Mutations within the genes MITF and SNAI2 have been identified in WS2, whereas mutations of EDN3, EDNRB, and SOX10 have been observed in patients with WS4. However, not all cases are explained at the molecular level, which raises the possibility that other genes are involved or that some mutations within the known genes are not detected by commonly used genotyping methods. We used a combination of semiquantitative fluorescent multiplex polymerase chain reaction and fluorescent in situ hybridization to search for SOX10 heterozygous deletions. We describe the first characterization of SOX10 deletions in patients presenting with WS4. We also found SOX10 deletions in WS2 cases, making SOX10 a new gene of WS2. Interestingly, neurological phenotypes reminiscent of that observed in WS4 (PCWH syndrome [peripheral demyelinating neuropathy, central dysmyelinating leukodystrophy, WS, and Hirschsprung disease]) were observed in some WS2-affected patients with SOX10 deletions. This study further characterizes the molecular complexity and the close relationship that links the different subtypes of WS.

  12. USH1K, a novel locus for type I Usher syndrome, maps to chromosome 10p11.21-q21.1.

    Science.gov (United States)

    Jaworek, Thomas J; Bhatti, Rashid; Latief, Noreen; Khan, Shaheen N; Riazuddin, Saima; Ahmed, Zubair M

    2012-10-01

    We ascertained two large Pakistani consanguineous families (PKDF231 and PKDF608) segregating profound hearing loss, vestibular dysfunction, and retinitis pigmentosa; the defining features of Usher syndrome type 1 (USH1). To date, seven USH1 loci have been reported. Here, we map a novel locus, USH1K, on chromosome 10p11.21-q21.1. In family PKDF231, we performed a genome-wide linkage screen and found a region of homozygosity shared among the affected individuals at chromosome 10p11.21-q21.1. Meiotic recombination events in family PKDF231 define a critical interval of 11.74 cM (20.20 Mb) bounded by markers D10S1780 (63.83 cM) and D10S546 (75.57 cM). Affected individuals of family PKDF608 were also homozygous for chromosome 10p11.21-q21.1-linked STR markers. Of the 85 genes within the linkage interval, PCDH15, GJD4, FZD4, RET and LRRC18 were sequenced in both families, but no potential pathogenic mutation was identified. The USH1K locus overlaps the non-syndromic deafness locus DFNB33 raising the possibility that the two disorders may be caused by allelic mutations.

  13. Facts about the Cornea and Corneal Disease

    Science.gov (United States)

    ... most used keratoprosthesis. It is made of clear plastic and consists of three parts, with donor cornea ... that, if successful, will lead to a significant reduction in the transmission of HSV to the cornea. ...

  14. Combining Sodium Hyaluronate and Polyvinylpyrrolidone Therapies for the Rabbit Cornea: A New Approach to Relief of the Human Dry Eye Syndrome.

    Science.gov (United States)

    Ehrenberg, Moshe; Zolotariov, Eyal; Loeb, Emmanuel; Poliansky, Vadim; Levy, Aharon

    2015-09-01

    The novel combination of 0.1% sodium hyaluronate (HA) and 5.0% polyvinylpyrrolidone (PVP) into one eyedrop was investigated to test the hypothesis of its increased relief of dry eye syndrome (DES). We evaluated HA and PVP, either alone, or in combination, by utilizing 16 rabbits, where their right eyes received one or two different eyedrops, and their left eyes, as controls, received none. The DES replica in rabbits was induced by 0.1% benzalkonium chloride (BAC) eyedrops. BAC was instilled into the right eyes of all rabbits, which were divided into four groups of four. In Group 1 M, the rabbits received only BAC. A second eyedrop given to the right eyes of Group 2 M was HA, of Group 3 M was PVP, and of Group 4 M was the combination of both HA and PVP. All eyes were followed clinically for 14 d, and thereafter, examined histopathologically. Clinically, the HA+PVP combination yielded the least perilimbal conjunctival erythema (p eyes in the combination group 4 M displayed the greatest preservation of the corneal epithelium (p < 0.001) and of the perilimbal conjunctival goblet cell density (p < 0.001). This unique combination of both HA and PVP into one eyedrop, was more potent than either treatment alone in protecting the ocular surface. A preparation, containing both HA and PVP may become useful for DES patients.

  15. ARL6IP6, a susceptibility locus for ischemic stroke, is mutated in a patient with syndromic Cutis Marmorata Telangiectatica Congenita.

    Science.gov (United States)

    Abumansour, Iman S; Hijazi, Hadia; Alazmi, Anas; Alzahrani, Fatma; Bashiri, Fahad A; Hassan, Hamdy; Alhaddab, Mohammed; Alkuraya, Fowzan S

    2015-08-01

    Cutis Marmorata Telangiectatica Congenita (CMTC) is a congenital localized or generalized vascular anomaly, usually sporadic in occurrence. It can be associated with other cutaneous or systemic manifestations. About 300 cases have been reported. The molecular etiology remains largely unknown. The main purpose of this study is to delineate the molecular basis for a syndromic CMTC phenotype in a consanguineous Saudi family. Clinical phenotyping including detailed neurological imaging, followed by autozygosity mapping and trio whole exome sequencing (WES) are also studied. We have identified a homozygous truncating mutation in ARL6IP6 as the likely cause of a syndromic form of CMTC associated with major dysmorphism, developmental delay, transient ischemic attacks and cerebral vascular malformations. This gene was previously implicated by genome wide association study (GWAS) as a susceptibility locus to ischemic stroke in young adults. We identify ARL6IP6 as a novel candidate gene for a syndromic form of CMTC. This suggests that ischemic stroke or transient ischemic attacks (TIA) may represent, at least in some cases, the mild end of a phenotypic spectrum that has at its severe end autosomal recessive CMTC. This finding contributes to a growing appreciation of the continuum of Mendelian and common complex diseases.

  16. Identification of a distinct type IV collagen α chain with restricted kidney distribution and assignment of its gene to the locus of X chromosome-linked Alport syndrome

    International Nuclear Information System (INIS)

    Hostikka, S.L.; Hoeyhtyae, M.; Tryggvason, K.; Eddy, R.L.; Byers, M.G.; Shows, T.B.

    1990-01-01

    The authors have identified and extensively characterized a type IV collagen α chain, referred to as α5(IV). Four overlapping cDNA clones isolated contain an open reading frame for 543 amino acid residues of the carboxyl-terminal end of a collagenous domain, a 229-residue carboxyl-terminal noncollagenous domain, and 1201 base pairs coding for a 3' untranslated region. The collagenous Gly-Xaa-Yaa repeat sequence has five imperfections that coincide with those in the corresponding region of the α1(IV) chain. The noncollagenous domain has 12 conserved cysteine residues and 83% and 63% sequence identity with the noncollagenous domains of the α1(IV) and α2(IV) chains, respectively. The α5(IV) chain has less sequence identity with the putative bovine α3(IV) and α4(IV) chains. Antiserum against an α5(IV) synthetic peptide stained a polypeptide chain of about 185 kDa by immunoblot analysis and immunolocalization of the chain in human kidney was almost completely restricted to the glomerulus. The gene was assigned to the Xq22 locus by somatic cell hybrids and in situ hybridization. This may be identical or close to the locus of the X chromosome-linked Alport syndrome that is believed to be a type IV collagen disease

  17. Hirschsprung disease, microcephaly, mental retardation, and characteristic facial features: delineation of a new syndrome and identification of a locus at chromosome 2q22-q23.

    Science.gov (United States)

    Mowat, D R; Croaker, G D; Cass, D T; Kerr, B A; Chaitow, J; Adès, L C; Chia, N L; Wilson, M J

    1998-01-01

    We have identified six children with a distinctive facial phenotype in association with mental retardation (MR), microcephaly, and short stature, four of whom presented with Hirschsprung (HSCR) disease in the neonatal period. HSCR was diagnosed in a further child at the age of 3 years after investigation for severe chronic constipation and another child, identified as sharing the same facial phenotype, had chronic constipation, but did not have HSCR. One of our patients has an interstitial deletion of chromosome 2, del(2)(q21q23). These children strongly resemble the patient reported by Lurie et al with HSCR and dysmorphic features associated with del(2)(q22q23). All patients have been isolated cases, suggesting a contiguous gene syndrome or a dominant single gene disorder involving a locus for HSCR located at 2q22-q23. Review of published reports suggests that there is significant phenotypic and genetic heterogeneity within the group of patients with HSCR, MR, and microcephaly. In particular, our patients appear to have a separate disorder from Goldberg-Shprintzen syndrome, for which autosomal recessive inheritance has been proposed because of sib recurrence and consanguinity in some families. Images PMID:9719364

  18. Physical mapping of the split hand/split foot (SHSF) locus on chromosome 7 reveals a relationship between SHSF and the syndromic ectrodactylies

    Energy Technology Data Exchange (ETDEWEB)

    Poorkaj, P.; Nunes, M.E.; Geshuri, D. [Univ. of Washington, Seattle, WA (United States)] [and others

    1994-09-01

    Split hand/split foot (also knows as ectrodactyly) is a human developmental malformation characterized by missing digits and claw-like extremities. An autosomal dominant form of this disorder has been mapped to 7q21.3-q22.1 on the basis of SHSF-associated chromosomal rearrangements: this locus has been designated SHFD1. We have constructed a physical map of the SHFD1 region that consists of contiguous yeast artificial chromosome clones and spans approximately 8 Mb. Somatic cell hybrid and fluorescent in situ hybridization analyses were used to define SHSF-associated chromosomal breakpoints in fourteen patients. A critical interval of about 1 Mb was established for SHFD1 by analysis of six patients with deletions. Translocation and inversion breakpoints in seven other patients were found to localize within a 500-700 kb interval within the critical region. Several candidate genes including DLX5 and DLX6 (members of the Drosophilia Distal-less homeobox-containing gene family) localize to this region. At least four of these genes are expressed in the developing mouse limb bud. Of particular interest is the observation that 8 of the 14 patients studied have syndromic ectrodactyly, which is characterized by the association of SHSF with a variety of other anomalies including cleft lip/palate, ectodermal dysplasia, and renal anomalies. Thus, these data implicate a single gene or cluster of genes at the SHFD1 locus in a wide range of developmental processes and serve to establish a molecular genetic relationship between simple SHSF and a broad group of human birth defects.

  19. Identification of a Sjögren's syndrome susceptibility locus at OAS1 that influences isoform switching, protein expression, and responsiveness to type I interferons.

    Directory of Open Access Journals (Sweden)

    He Li

    2017-06-01

    Full Text Available Sjögren's syndrome (SS is a common, autoimmune exocrinopathy distinguished by keratoconjunctivitis sicca and xerostomia. Patients frequently develop serious complications including lymphoma, pulmonary dysfunction, neuropathy, vasculitis, and debilitating fatigue. Dysregulation of type I interferon (IFN pathway is a prominent feature of SS and is correlated with increased autoantibody titers and disease severity. To identify genetic determinants of IFN pathway dysregulation in SS, we performed cis-expression quantitative trait locus (eQTL analyses focusing on differentially expressed type I IFN-inducible transcripts identified through a transcriptome profiling study. Multiple cis-eQTLs were associated with transcript levels of 2'-5'-oligoadenylate synthetase 1 (OAS1 peaking at rs10774671 (PeQTL = 6.05 × 10-14. Association of rs10774671 with SS susceptibility was identified and confirmed through meta-analysis of two independent cohorts (Pmeta = 2.59 × 10-9; odds ratio = 0.75; 95% confidence interval = 0.66-0.86. The risk allele of rs10774671 shifts splicing of OAS1 from production of the p46 isoform to multiple alternative transcripts, including p42, p48, and p44. We found that the isoforms were differentially expressed within each genotype in controls and patients with and without autoantibodies. Furthermore, our results showed that the three alternatively spliced isoforms lacked translational response to type I IFN stimulation. The p48 and p44 isoforms also had impaired protein expression governed by the 3' end of the transcripts. The SS risk allele of rs10774671 has been shown by others to be associated with reduced OAS1 enzymatic activity and ability to clear viral infections, as well as reduced responsiveness to IFN treatment. Our results establish OAS1 as a risk locus for SS and support a potential role for defective viral clearance due to altered IFN response as a genetic pathophysiological basis of this complex autoimmune disease.

  20. Identification of a Sjögren's syndrome susceptibility locus at OAS1 that influences isoform switching, protein expression, and responsiveness to type I interferons

    Science.gov (United States)

    Li, He; Reksten, Tove Ragna; Ice, John A.; Kelly, Jennifer A.; Adrianto, Indra; Wang, Shaofeng; He, Bo; Grundahl, Kiely M.; Glenn, Stuart B.; Miceli-Richard, Corinne; Bowman, Simon; Lester, Sue; Eriksson, Per; Brun, Johan G.; Gøransson, Lasse G.; Harboe, Erna; Guthridge, Joel M.; Patel, Ketan; Adler, Adam J.; Farris, A. Darise; Brennan, Michael T.; Chodosh, James; Gopalakrishnan, Rajaram; Weisman, Michael H.; Venuturupalli, Swamy; Wallace, Daniel J.; Hefner, Kimberly S.; Houston, Glen D.; Hughes, Pamela J.; Lewis, David M.; Radfar, Lida; Vista, Evan S.; Rohrer, Michael D.; Stone, Donald U.; Vyse, Timothy J.; Harley, John B.; James, Judith A.; Turner, Sean; Alevizos, Ilias; Anaya, Juan-Manuel; Rhodus, Nelson L.; Segal, Barbara M.; Montgomery, Courtney G.; Scofield, R. Hal; Kovats, Susan; Mariette, Xavier; Witte, Torsten; Rischmueller, Maureen; Omdal, Roald; Lessard, Christopher J.; Sivils, Kathy L.

    2017-01-01

    Sjögren’s syndrome (SS) is a common, autoimmune exocrinopathy distinguished by keratoconjunctivitis sicca and xerostomia. Patients frequently develop serious complications including lymphoma, pulmonary dysfunction, neuropathy, vasculitis, and debilitating fatigue. Dysregulation of type I interferon (IFN) pathway is a prominent feature of SS and is correlated with increased autoantibody titers and disease severity. To identify genetic determinants of IFN pathway dysregulation in SS, we performed cis-expression quantitative trait locus (eQTL) analyses focusing on differentially expressed type I IFN-inducible transcripts identified through a transcriptome profiling study. Multiple cis-eQTLs were associated with transcript levels of 2'-5'-oligoadenylate synthetase 1 (OAS1) peaking at rs10774671 (PeQTL = 6.05 × 10−14). Association of rs10774671 with SS susceptibility was identified and confirmed through meta-analysis of two independent cohorts (Pmeta = 2.59 × 10−9; odds ratio = 0.75; 95% confidence interval = 0.66–0.86). The risk allele of rs10774671 shifts splicing of OAS1 from production of the p46 isoform to multiple alternative transcripts, including p42, p48, and p44. We found that the isoforms were differentially expressed within each genotype in controls and patients with and without autoantibodies. Furthermore, our results showed that the three alternatively spliced isoforms lacked translational response to type I IFN stimulation. The p48 and p44 isoforms also had impaired protein expression governed by the 3' end of the transcripts. The SS risk allele of rs10774671 has been shown by others to be associated with reduced OAS1 enzymatic activity and ability to clear viral infections, as well as reduced responsiveness to IFN treatment. Our results establish OAS1 as a risk locus for SS and support a potential role for defective viral clearance due to altered IFN response as a genetic pathophysiological basis of this complex autoimmune disease. PMID

  1. A new locus for Seckel syndrome on chromosome 18p11.31-q11.2

    DEFF Research Database (Denmark)

    Børglum, Anders; Balslev, Thomas; Haagerup, Annette

    2001-01-01

    Seckel syndrome (MIM 210600) is a rare autosomal recessive disorder with a heterogeneous appearance. Key features are growth retardation, microcephaly with mental retardation, and a characteristic 'bird-headed' facial appearance. We have performed a genome-wide linkage scan in a consanguineous fa...

  2. Monogenic diabetes syndromes: Locus-specific databases for Alström, Wolfram, and Thiamine-responsive megaloblastic anemia.

    Science.gov (United States)

    Astuti, Dewi; Sabir, Ataf; Fulton, Piers; Zatyka, Malgorzata; Williams, Denise; Hardy, Carol; Milan, Gabriella; Favaretto, Francesca; Yu-Wai-Man, Patrick; Rohayem, Julia; López de Heredia, Miguel; Hershey, Tamara; Tranebjaerg, Lisbeth; Chen, Jian-Hua; Chaussenot, Annabel; Nunes, Virginia; Marshall, Bess; McAfferty, Susan; Tillmann, Vallo; Maffei, Pietro; Paquis-Flucklinger, Veronique; Geberhiwot, Tarekign; Mlynarski, Wojciech; Parkinson, Kay; Picard, Virginie; Bueno, Gema Esteban; Dias, Renuka; Arnold, Amy; Richens, Caitlin; Paisey, Richard; Urano, Fumihiko; Semple, Robert; Sinnott, Richard; Barrett, Timothy G

    2017-07-01

    We developed a variant database for diabetes syndrome genes, using the Leiden Open Variation Database platform, containing observed phenotypes matched to the genetic variations. We populated it with 628 published disease-associated variants (December 2016) for: WFS1 (n = 309), CISD2 (n = 3), ALMS1 (n = 268), and SLC19A2 (n = 48) for Wolfram type 1, Wolfram type 2, Alström, and Thiamine-responsive megaloblastic anemia syndromes, respectively; and included 23 previously unpublished novel germline variants in WFS1 and 17 variants in ALMS1. We then investigated genotype-phenotype relations for the WFS1 gene. The presence of biallelic loss-of-function variants predicted Wolfram syndrome defined by insulin-dependent diabetes and optic atrophy, with a sensitivity of 79% (95% CI 75%-83%) and specificity of 92% (83%-97%). The presence of minor loss-of-function variants in WFS1 predicted isolated diabetes, isolated deafness, or isolated congenital cataracts without development of the full syndrome (sensitivity 100% [93%-100%]; specificity 78% [73%-82%]). The ability to provide a prognostic prediction based on genotype will lead to improvements in patient care and counseling. The development of the database as a repository for monogenic diabetes gene variants will allow prognostic predictions for other diabetes syndromes as next-generation sequencing expands the repertoire of genotypes and phenotypes. The database is publicly available online at https://lovd.euro-wabb.org. © 2017 The Authors. **Human Mutation published by Wiley Periodicals, Inc.

  3. Cornea procurement, preservation and transplantation

    International Nuclear Information System (INIS)

    Hudson Silva

    1999-01-01

    Our experience on this subject is 40 years and we have seen the developments everywhere during this total period. Cornea procurement has been an unsurmountable problem in a large number of countries, mostly due to social and cultural reasons. The requirements for a simple eye bank to manage the supply for a local hospital are minimal. What is the most important is the donor base. In Sri Lanka nurtured in the traditions of Theravada Buddhism the donor base was easy to prepare. We had no difficulties with Christians and Hindus. For Muslims there are Fatwas in favour of donating eyes. But we always found them to be a reluctant group. But in predominantly Muslim countries, it is imperative that social workers should take up this issue, so those thousands may be helped. In all areas where attempts are made to procure comeas, it is important to have a day-and-night service available at short notice to collect any eyes offered. A trained technician with sterilised instruments to obtain eyes and blood sample must be available at a convenient location preferably in a large hospital. Even in places where the supply is infrequent, it is essential to have the readily-sterilised instruments to proceed to a donor site at short notice. To get eyes, general publicity in mass media alone is not sufficient. Such publicity makes people aware of the need for donor eyes and where a technician/doctor is available. What is more important is to canvass personally after a person has died For this purpose trained social workers may be employed, or the technician can do the motivation, as we do in Sri Lanka. Once eyes are removed, it is essential to pay careful attention to the appearance of the cadaver. It should not (and need not) cause any deformity as such event has a profound negative effect on the campaign. Many different preservation methods have been used over the years. Mc Carey-Kaufmann (MK) medium has been the standard for many years, and gives a life span of 4-5 days. The formula

  4. Linkage disequilibrium between an allele at the dopamine D4 receptor locus and Tourette syndrome, by the transmission-disequilibrium test

    Energy Technology Data Exchange (ETDEWEB)

    Grice, D.E.; Gelernter, J. [Veterans Administration Connecticut Healthcare System, West Haven, CT (United States); Leckman, J.F.; Pauls, D.L. [Yale Univ. School of Medicine, New Haven, CT (United States)] [and others

    1996-09-01

    Dopaminergic abnormalities are implicated in the pathogenesis of Tourette syndrome (TS) and chronic multiple tics. We used the transmission-disequilibrium test (TDT) method to test for linkage disequilibrium between a specific allele (the seven-repeat allele (DRD4*7R) of the exon 3 VNTR polymorphic site) at the D4 dopamine receptor locus (DRD4) and expression of chronic multiple tics and TS. This particular allele had been shown in functional studies to have different binding properties compared with the other common alleles in this DRD4 polymorphic system. We studied 64 family trios (consisting of an affected person and two parents, at least one heterozygous for DRD4*7R), including 12 nuclear family trios and 52 trios from four large TS kindreds. The DRD4*7R allele was transmitted significantly more frequently than expected ({chi}{sup 2}{sub TDT} ranging from 8.47 [P < .004] to 10.80 [P = .001], depending on breadth of disease definition and inclusion or exclusion of inferred genotypes). Confirmation of this finding will depend on either replication in other samples or the identification of a transmitted functional mutation within this sample. 56 refs., 2 figs., 3 tabs.

  5. Anatomy and physiology of the cornea.

    Science.gov (United States)

    DelMonte, Derek W; Kim, Terry

    2011-03-01

    The importance of the cornea to the ocular structure and visual system is often overlooked because of the cornea's unassuming transparent nature. The cornea lacks the neurobiological sophistication of the retina and the dynamic movement of the lens; yet, without its clarity, the eye would not be able to perform its necessary functions. The complexity of structure and function necessary to maintain such elegant simplicity is the wonder that draws us to one of the most important components of our visual system. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  6. Heterozygous deletion at the SOX10 gene locus in two patients from a Chinese family with Waardenburg syndrome type II.

    Science.gov (United States)

    Wenzhi, He; Ruijin, Wen; Jieliang, Li; Xiaoyan, Ma; Haibo, Liu; Xiaoman, Wang; Jiajia, Xian; Shaoying, Li; Shuanglin, Li; Qing, Li

    2015-10-01

    Waardenburg syndrome (WS) is a rare disease characterized by sensorineural deafness and pigment disturbance. To date, almost 100 mutations have been reported, but few reports on cases with SOX10 gene deletion. The inheritance pattern of SOX10 gene deletion is still unclear. Our objective was to identify the genetic causes of Waardenburg syndrome type II in a two-generation Chinese family. Clinical evaluations were conducted in both of the patients. Microarray analysis and multiplex ligation-dependent probe amplification (MLPA) were performed to identify disease-related copy number variants (CNVs). DNA sequencing of the SOX10, MITF and SNAI2 genes was performed to identify the pathogenic mutation responsible for WS2. A 280kb heterozygous deletion at the 22q13.1 chromosome region (including SOX10) was detected in both of the patients. No mutation was found in the patients, unaffected family members and 30 unrelated healthy controls. This report is the first to describe SOX10 heterozygous deletions in Chinese WS2 patients. Our result conform the thesis that heterozygous deletions at SOX10 is an important pathogenicity for WS, and present as autosomal dominant inheritance. Nevertheless, heterozygous deletion of the SOX10 gene would be worth investigating to understand their functions and contributions to neurologic phenotypes. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Diagnosis of the fragile X syndrome in males using methylation-specific PCR of the FMRI locus

    Directory of Open Access Journals (Sweden)

    Sérgio D.J. Pena

    1999-06-01

    Full Text Available We have developed a non-isotopic technique based on methylation-specific PCR (MSP of the FMR1 promoter for the identification of fragile X full mutations among men. DNA samples were first treated with sodium bisulfite to convert unmethylated, but not methylated, cytosines to uracil, followed by PCR amplification with oligonucleotide primers specific for methylated versus unmethylated DNA. We designed two primer pairs: one produced a 142-bp fragment from the bisulfite-treated methylated CpG island, while the other generated an 84-bp product from the treated non-methylated promoter. In normal males only the 84-bp fragment was seen, while the diagnosis of FRAXA was doubly indicated by the appearance of a 142-bp product together with absence or weak visualization of the 84-bp band. As an indispensable internal control for the efficiency of the sodium bisulfite treatment, we used a primer pair specific for the imprinted maternal methylated version of the CpG island of the SNRPN gene on human chromosome 15. Using the methylation-specific PCR we identified with 100% sensitivity and accuracy eight previously diagnosed FRAXA male patients mixed with 42 normal controls. Because of its simplicity and high efficiency, methylation-specific PCR may become the method of choice for the diagnosis of the fragile X syndrome in mentally retarded males.Nós desenvolvemos uma técnica não-isotópica baseada na PCR para a identificação de mutações completas da síndrome do X-frágil em homens. O método é baseado na PCR específica para metilação do promotor do gene FMR1. Amostras de DNA são tratadas com bissulfito de sódio para converter citosinas não-metiladas para uracilo, seguindo-se amplificação por PCR com oligonucleotídeos iniciadores específicos para DNA metilado versus não-metilado. Desenhamos dois iniciadores: um produz um fragmento de 142 pb da ilha CpG metilada tratada com bissulfito de sódio, enquanto o outro gera um produto de 84 pb do

  8. Spherical aberrations of human astigmatic corneas.

    Science.gov (United States)

    Zhao, Huawei; Dai, Guang-Ming; Chen, Li; Weeber, Henk A; Piers, Patricia A

    2011-11-01

    To evaluate whether the average spherical aberration of human astigmatic corneas is statistically equivalent to human nonastigmatic corneas. Spherical aberrations of 445 astigmatic corneas prior to laser vision correction were retrospectively investigated to determine Zernike coefficients for central corneal areas 6 mm in diameter using CTView (Sarver and Associates). Data were divided into groups according to cylinder power (0.01 to 0.25 diopters [D], 0.26 to 0.75 D, 0.76 to 1.06 D, 1.07 to 1.53 D, 1.54 to 2.00 D, and >2.00 D) and according to age by decade. Spherical aberrations were correlated with age and astigmatic power among groups and the entire population. Statistical analyses were conducted, and P.05 for all tested groups). Mean spherical aberration of astigmatic corneas was not correlated significantly with cylinder power or age (P>.05). Spherical aberrations are similar to those of nonastigmatic corneas, permitting the use of these additional data in the design of aspheric toric intra-ocular lenses. Copyright 2011, SLACK Incorporated.

  9. Comparison of endothelial cell density of organ cultured corneas with cornea donor study.

    Science.gov (United States)

    Campolmi, Nelly; He, Zhiguo; Acquart, Sophie; Trone, Marie-Caroline; Bernard, Aurélien; Gauthier, Anne-Sophie; Garraud, Olivier; Forest, Fabien; Péocʼh, Michel; Gain, Philippe; Thuret, Gilles

    2014-06-01

    Determination of the endothelial cell density (ECD) by eye banks is paramount in donor cornea qualification. Unbiased measurement avoids wastage and grafts with an increased risk of premature failure. Internal calibration of the counting method is essential, but external validation would add an extra stage in the assessment of reliability. In this respect, data published by the multicenter Cornea Donor Study (CDS) in 2005 is a reference. The aim of the study was to compare ECD determined within a single eye bank, which uses calibrated image analysis software designed for transmitted light microscopy images of organ cultured corneas, with the CDS data determined on specular microscopy images of corneas stored at 4°C. ECD of consecutive corneas retrieved between 2005 and 2013 was determined after exposure to 0.9% NaCl. More than 300 ECs were counted on 3 fields of the central 8 mm. Endothelial cell boundaries were automatically drawn and verified by a skilled technician who performed all necessary corrections. Three thousand fifty-two corneas were analyzed, of which 48.5% donors were >75 years (CDS upper age limit). Between 10 and 75 years, the ECD varied according to donor age exactly in the same manner as in the CDS, but were consistently higher of 100 ± 25 cells per square millimeter (P Atlantic Ocean could be due to (1) differences in counting principles and/or (2) higher shrinkage of the cornea caused by stromal edema in organ culture.

  10. GENDER AND AGE RELATED VARIATION IN CORNEA POWER

    African Journals Online (AJOL)

    2014-05-01

    May 1, 2014 ... population and how it varies with gender and age. Design: A .... horizontal in orientation. For the purpose of .... race as cornea curvature have been noted to exhibit ... Grosevenor, T. Role of Cornea in Emmetropia and. Myopia.

  11. 3D Architecture, dynamics as well as functional implications of genome organization of the Prader-Willi/Angelmann syndrome region & the Immunoglobin Heavy-Chain locus

    NARCIS (Netherlands)

    T.A. Knoch (Tobias)

    2008-01-01

    textabstractThe general 3D architecture of the immunoglobin heavy-chain (Igh) locus was determined by a novel interdisciplinary combination of high-resolution FISH and high-resolution epifluorescence spectral distance microscopy with analytical analysis, computer simulations, as well as

  12. Lectin receptors in the human cornea.

    Science.gov (United States)

    Holmes, M J; Mannis, M J; Lund, J; Jacobs, L

    Five different biotin labeled lectins, Concanavalin-A (Con A), wheat germ agglutinin (WGA), Ricinus communis agglutinin I (RCA1), Ulex europaeus agglutinin (UEA1), and soybean agglutinin (SBA) were used to study lectin receptors on formalin-fixed paraffin embedded human corneas. Con A stained the cytoplasm, cell, and nuclear membranes of the epithelial cells and stained the stroma diffusely. WGA stained the superficial epithelial cells, the epithelial cell membranes, and the keratocytes of the stroma. SBA did not react with any of the corneal layers. RCA1 heavily stained the keratocytes but did not stain the epithelium. UEA1 lightly stained the epithelial cell cytoplasm and interstitial stroma. All staining reactions could be abolished by omission of the lectin or by the use of the appropriate inhibitory sugar. The lectin binding patterns reported here provide a means for further investigation of carbohydrate structures in the human cornea in both normal and disease states.

  13. Diffusion of protein through the human cornea.

    Science.gov (United States)

    Charalel, Resmi A; Engberg, Kristin; Noolandi, Jaan; Cochran, Jennifer R; Frank, Curtis; Ta, Christopher N

    2012-01-01

    To determine the rate of diffusion of myoglobin and bovine serum albumin (BSA) through the human cornea. These small proteins have hydrodynamic diameters of approximately 4.4 and 7.2 nm, and molecular weights of 16.7 and 66 kDa, for myoglobin and BSA, respectively. Diffusion coefficients were measured using a diffusion chamber where the protein of interest and balanced salt solution were in different chambers separated by an ex vivo human cornea. Protein concentrations in the balanced salt solution chamber were measured over time. Diffusion coefficients were calculated using equations derived from Fick's law and conservation of mass in a closed system. Our experiments demonstrate that the diffusion coefficient of myoglobin is 5.5 ± 0.9 × 10(-8) cm(2)/s (n = 8; SD = 1.3 × 10(-8) cm(2)/s; 95% CI: 4.6 × 10(-8) to 6.4 × 10(-8) cm(2)/s) and the diffusion coefficient of BSA is 3.1 ± 1.0 × 10(-8) cm(2)/s (n = 8; SD = 1.4 × 10(-8) cm(2)/s; 95% CI: 2.1 × 10(-8) to 4.1 × 10(-8) cm(2)/s). Our study suggests that molecules as large as 7.2 nm may be able to passively diffuse through the human cornea. With applications in pharmacotherapy and the development of an artificial cornea, further experiments are warranted to fully understand the limits of human corneal diffusion and its clinical relevance. Copyright © 2012 S. Karger AG, Basel.

  14. N-ethyl-N-nitrosourea-induced null mutation at the mouse Car-2 locus: An animal model for human carbonic anhydrase II deficiency syndrome

    International Nuclear Information System (INIS)

    Lewis, S.E.; Barnett, L.B.; Erickson, R.P.; Venta, P.J.; Tashian, R.E.

    1988-01-01

    Electrophoretic screening of (C57BL/6J x DBA/2J)F 1 progeny of male mice treated with N-ethyl-N-nitrosourea revealed a mouse that lacked the paternal carbonic anhydrase II (Ca II). Breeding tests showed that this trait was heritable and due to a null mutation at the Car-2 locus on chromosome 3. Like humans with the same inherited enzyme defect, animals homozygous for the new null allele are runted and have renal tubular acidosis. However, the prominent osteopetrosis found in humans with CA II deficiency could be detected even in very old homozygous null mice. A molecular analysis of the deficient mice shows that the mutant gene is not deleted and is transcribed. The CA II protein, which is normally expressed in most tissues, could not be detected by immunodiffusion analysis in any tissues of the CA II-deficient mice, suggesting a nonsense or a missense mutation at the Car-2 locus

  15. Factors influencing the contamination rate of human organ-cultured corneas.

    Science.gov (United States)

    Röck, Daniel; Wude, Johanna; Bartz-Schmidt, Karl U; Yoeruek, Efdal; Thaler, Sebastian; Röck, Tobias

    2017-12-01

    To assess the influence of donor, environment and storage factors on the contamination rate of organ-cultured corneas, to consider the microbiological species causing corneal contamination and to investigate the corresponding sensitivities. Data from 1340 consecutive donor corneas were analysed retrospectively. Logistic regression analysis was used to assess the influence of different factors on the contamination rate of organ-cultured corneas for transplantation. The mean annual contamination rate was 1.8 ± 0.4% (range: 1.3-2.1%); 50% contaminations were of fungal origin with exclusively Candida species, and 50% contaminations were of bacterial origin with Staphylococcus species being predominant. The cause of donor death including infection and multiple organ dysfunction syndrome increased the risk of bacterial or fungal contamination during organ culture (p = 0.007 and p = 0.014, respectively). Differentiating between septic and aseptic donors showed an increased risk of contamination for septic donors (p = 0.0020). Mean monthly temperature including warmer months increased the risk of contamination significantly (p = 0.0031). Sex, donor age, death to enucleation, death to corneoscleral disc excision and storage time did not increase the risk of contamination significantly. The genesis of microbial contamination in organ-cultured donor corneas seems to be multifactorial. The main source of fungal or bacterial contamination could be resident species from the skin flora. The rate of microbial contamination in organ-cultured donor corneas seems to be dependent on the cause of donor death and mean monthly temperature. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  16. Localization of A Novel Autosomal Recessive Non-Syndromic Hearing Impairment Locus (DFNB38) to 6q26–q27 in a Consanguineous Kindred from Pakistan

    OpenAIRE

    Ansar, Muhammad; Ramzan, Mohammad; Pham, Thanh L.; Yan, Kai; Jamal, Syed Muhammad; Haque, Sayedul; Ahmad, Wasim; Leal, Suzanne M.

    2003-01-01

    For autosomal recessive nonsyndromic hearing impairment over 30 loci have been mapped and 19 genes have been identified. DFNB38, a novel locus for autosomal recessive nonsyndromic hearing impairment, was localized in a consanguineous Pakistani kindred to 6q26–q27. The affected family members present with profound prelingual sensorineural hearing impairment and use sign language for communications. Linkage was established to microsatellite markers located on chromosome 6q26–q27 (Multipoint lod...

  17. Dynamic Sensing of Cornea Deformation during an Air Puff

    Science.gov (United States)

    Yamada, Kenji; Yamasaki, Naoyuki; Gosho, Takumi; Kiuchi, Yoshiaki; Takenaka, Jouji; Higashimori, Mitsuru; Kaneko, Makoto

    In early diagnosis of glancoma, intraocular pressure measurement is one of an important method. Non-contact method has measured eye pressure through the deformation of cornea during the increase of the force due to air puff. The deformation is influenced by the cornea stiffness as well as the eye internal pressure. Since the cornea stiffness is unknown in general, it is difficult to evaluate the ture eye pressure. The dynamic behavior of cornea under air puff may provide us with a good hint for evaluating the cornea stiffness appropriately. For this purpose, we develop the sensing system composed of a high speed camera, a mirror for producing a virtual camera, a non-contact tonometer and a slit light source. This system enables us to measure the cornea deformation under concave shape. We show the experimental data for human eyes as well as an artificial eye made by transparent material.

  18. Prenatal diagnosis of the fragile X syndrome : loss of mutation owing to a double recombinant or gene conversion event at the FMR1 locus

    NARCIS (Netherlands)

    Losekoot, M; Hoogendoorn, E; Olmer, R; Jansen, CCAM; Oosterwijk, JC; vandenOuweland, AMW; Halley, DJJ; Warren, ST; Willemsen, R; Oostra, BA; Bakker, E

    1997-01-01

    The fragile X syndrome, an X linked mental retardation syndrome, is caused by an expanded CGG repeat in the first exon of the FMR1 gene. In patients with an expanded repeat the FMR1 promoter is methylated and, consequently, the gene is silenced and no FMR1 protein (FMRP) is produced, thus leading to

  19. Excimer laser ablation of the cornea

    Science.gov (United States)

    Pettit, George H.; Ediger, Marwood N.; Weiblinger, Richard P.

    1995-03-01

    Pulsed ultraviolet laser ablation is being extensively investigated clinically to reshape the optical surface of the eye and correct vision defects. Current knowledge of the laser/tissue interaction and the present state of the clinical evaluation are reviewed. In addition, the principal findings of internal Food and Drug Administration research are described in some detail, including a risk assessment of the laser-induced-fluorescence and measurement of the nonlinear optical properties of cornea during the intense UV irradiation. Finally, a survey is presented of the alternative laser technologies being explored for this ophthalmic application.

  20. QTL for white spot syndrome virus resistance and the sex-determining locus in the Indian black tiger shrimp (Penaeus monodon).

    Science.gov (United States)

    Robinson, Nicholas A; Gopikrishna, Gopalapillay; Baranski, Matthew; Katneni, Vinaya Kumar; Shekhar, Mudagandur S; Shanmugakarthik, Jayakani; Jothivel, Sarangapani; Gopal, Chavali; Ravichandran, Pitchaiyappan; Gitterle, Thomas; Ponniah, Alphis G

    2014-08-28

    Shrimp culture is a fast growing aquaculture sector, but in recent years there has been a shift away from tiger shrimp Penaeus monodon to other species. This is largely due to the susceptibility of P. monodon to white spot syndrome virus disease (Whispovirus sp.) which has impacted production around the world. As female penaeid shrimp grow more rapidly than males, mono-sex production would be advantageous, however little is known about genes controlling or markers associated with sex determination in shrimp. In this study, a mapped set of 3959 transcribed single nucleotide polymorphisms were used to scan the P. monodon genome for loci associated with resistance to white-spot syndrome virus and sex in seven full-sibling tiger shrimp families challenged with white spot syndrome virus. Linkage groups 2, 3, 5, 6, 17, 18, 19, 22, 27 and 43 were found to contain quantitative trait loci significantly associated with hours of survival after white spot syndrome virus infection (P shrimp.

  1. Advanced Squamous Cell Carcinoma of Cornea in a Child with ...

    African Journals Online (AJOL)

    lids, conjunctiva, and cornea are affected by the disease process.[3] A case of XP ... In the left eye, almost the entire cornea was involved with a grayish-white, irregular, and ... referring to its characteristic dry pigmented skin. It was also named ...

  2. Finite element modelling of cornea mechanics: a review

    Directory of Open Access Journals (Sweden)

    Talisa Mohammad Nejad

    2014-01-01

    Full Text Available The cornea is a transparent tissue in front of the eye that refracts light and facilitates vision. A slight change in the geometry of the cornea remarkably affects the optical power. Because of this sensitivity, biomechanical study of the cornea can reveal much about its performance and function. In vivo and in vitro studies have been conducted to investigate the mechanics of the cornea and determine its characteristics. Numerical techniques such as the finite element method (FEM have been extensively implemented as effective and noninvasive methods for analyzing corneal mechanics and possible disorders. This article reviews the use of FEM for assessing the mechanical behavior of the cornea. Different applications of FEM in corneal disease studies, surgical predictions, impact simulations, and clinical applications have been reviewed. Some suggestions for the future of this type of modeling in the area of corneal mechanics are also discussed.

  3. [The 2009 performance report of the German cornea banks].

    Science.gov (United States)

    Schrage, N; Reinhard, T; Seitz, B; Hermel, M; Böhringer, D; Reinshagen, H

    2011-03-01

    In Germany, human tissue for corneal and amniotic transplantation is supplied by 27 cornea banks. The Section for Tissue Transplantation and Biotechnology of the German Ophthalmological Society records the cornea banks' activities by means of an annual questionnaire. In 2009, a total of 4,818 corneal grafts were processed by 21 responding cornea banks, and 57% were deemed suitable for transplantation. This ratio is slightly higher than the European average. In addition, German cornea banks released 1,257 amniotic grafts in 2009. German cornea banks are currently facing new regulatory issues due to updated legislation regarding tissue transplantation. Recent updates in European law have limited the cutoff time for postmortem blood sampling to 24 h, and this regulation may lead to a significant reduction in potential donors.

  4. Localization of A Novel Autosomal Recessive Non-Syndromic Hearing Impairment Locus (DFNB38) to 6q26–q27 in a Consanguineous Kindred from Pakistan

    Science.gov (United States)

    Ansar, Muhammad; Ramzan, Mohammad; Pham, Thanh L.; Yan, Kai; Jamal, Syed Muhammad; Haque, Sayedul; Ahmad, Wasim; Leal, Suzanne M.

    2010-01-01

    For autosomal recessive nonsyndromic hearing impairment over 30 loci have been mapped and 19 genes have been identified. DFNB38, a novel locus for autosomal recessive nonsyndromic hearing impairment, was localized in a consanguineous Pakistani kindred to 6q26–q27. The affected family members present with profound prelingual sensorineural hearing impairment and use sign language for communications. Linkage was established to microsatellite markers located on chromosome 6q26–q27 (Multipoint lod score 3.6). The genetic region for DFNB38 spans 10.1 cM according to the Marshfield genetic map and is bounded by markers D6S980 and D6S1719. This genetic region corresponds to 3.4 MB on the sequence-based physical map. PMID:12890929

  5. Rudolf Virchow's medical school dissertation on rheumatism and the cornea: overlooked tribute to the cornea in biomedical research.

    Science.gov (United States)

    Margo, Curtis E; Harman, Lynn E

    2015-02-01

    To critique Rudolf Virchow's medical school dissertation on rheumatism and the cornea and to determine whether it might have anticipated his remarkable career in medicine. Review of the English translation of Rudolf Virchow's de Rheumate Praesertim Corneae written in 1843. The dissertation was more than 7000 words long. Virchow considered rheumatism as an irritant disorder not induced by acid as traditionally thought but by albumin. He concluded that inflammation was secondary to a primary irritant and that the "seat" of rheumatism was "gelatinous" (connective) tissues, which included the cornea. He divided kerato-rheumatism into different varieties. The prognosis of keratitis was variable, and would eventually lapse into "scrofulosis, syphilis, or arthritis of the cornea." Virchow's dissertation characterizes rheumatism in terms of chemical and tissue interactions that make little sense in the context of today's knowledge of rheumatic disease and keratitis. Ironically, many of these concepts were made obsolete by the cellular model of disease that Virchow championed. Virchow decided to pursue the study of rheumatism through the cornea because he thought that the cornea was an ideal tissue to study disease. This discernment was passed on to his students whose seminal contributions to general pathology were based on research with the cornea. It is debatable whether Virchow's insight into the importance of the cornea in biomedical research at such an early stage of his career could have predicted his monumental contributions to medicine.

  6. Identification of a Sj?gren's syndrome susceptibility locus at OAS1 that influences isoform switching, protein expression, and responsiveness to type I interferons

    OpenAIRE

    Li, He; Reksten, Tove Ragna; Ice, John A.; Kelly, Jennifer A.; Adrianto, Indra; Rasmussen, Astrid; Wang, Shaofeng; He, Bo; Grundahl, Kiely M.; Glenn, Stuart B.; Miceli-Richard, Corinne; Bowman, Simon; Lester, Sue; Eriksson, Per; Eloranta, Maija-Leena

    2017-01-01

    Sjogrens syndrome (SS) is a common, autoimmune exocrinopathy distinguished by keratoconjunctivitis sicca and xerostomia. Patients frequently develop serious complications including lymphoma, pulmonary dysfunction, neuropathy, vasculitis, and debilitating fatigue. Dysregulation of type I interferon (IFN) pathway is a prominent feature of SS and is correlated with increased autoantibody titers and disease severity. To identify genetic determinants of IFN pathway dysregulation in SS, we performe...

  7. Image simulation using LOCUS

    International Nuclear Information System (INIS)

    Strachan, J.D.; Roberts, J.A.

    1989-09-01

    The LOCUS data base program has been used to simulate images and to solve simple equations. This has been accomplished by making each record (which normally would represent a data entry)represent sequenced or random number pairs

  8. Oxidative Stress to the Cornea, Changes in Corneal Optical Properties, and Advances in Treatment of Corneal Oxidative Injuries

    Czech Academy of Sciences Publication Activity Database

    Čejka, Čestmír; Čejková, Jitka

    2015-01-01

    Roč. 2015, Mar 11 (2015), s. 591530 ISSN 1942-0900 R&D Projects: GA ČR(CZ) GA14-12580S Keywords : experimental autoimmune uveitis * eye sjogrens-syndrome * rabbit cornea * aldehyde dehydrogenase * uvb rays * glutathione-peroxidase * superoxide-dismutase * refractive-index * reactive oxygen * alkali-burn Subject RIV: FF - HEENT, Dentistry Impact factor: 4.492, year: 2015

  9. Customized Finite Element Modelling of the Human Cornea.

    Directory of Open Access Journals (Sweden)

    Irene Simonini

    Full Text Available To construct patient-specific solid models of human cornea from ocular topographer data, to increase the accuracy of the biomechanical and optical estimate of the changes in refractive power and stress caused by photorefractive keratectomy (PRK.Corneal elevation maps of five human eyes were taken with a rotating Scheimpflug camera combined with a Placido disk before and after refractive surgery. Patient-specific solid models were created and discretized in finite elements to estimate the corneal strain and stress fields in preoperative and postoperative configurations and derive the refractive parameters of the cornea.Patient-specific geometrical models of the cornea allow for the creation of personalized refractive maps at different levels of IOP. Thinned postoperative corneas show a higher stress gradient across the thickness and higher sensitivity of all geometrical and refractive parameters to the fluctuation of the IOP.Patient-specific numerical models of the cornea can provide accurate quantitative information on the refractive properties of the cornea under different levels of IOP and describe the change of the stress state of the cornea due to refractive surgery (PRK. Patient-specific models can be used as indicators of feasibility before performing the surgery.

  10. Extracellular matrix alterations in human corneas with bullous keratopathy

    DEFF Research Database (Denmark)

    Ljubimov, A V; Burgeson, R E; Butkowski, R J

    1996-01-01

    PURPOSE. To uncover abnormalities of extracellular matrix (ECM) distribution in human corneas with pseudophakic and aphakic bullous keratopathy (PBK/ABK). METHODS. Indirect immunofluorescence with antibodies to 27 ECM components was used on frozen sections of 14 normal and 20 PBK/ABK corneas...... in some cases, correlated with decreased visual acuity. In normal central corneas, tenascin was never found. Other major ECM abnormalities in PBK/ABK corneas compared to normals included: discontinuous epithelial BM straining for laminin-1 (alpha 1 beta 1 gamma 1), entactin/nidogen and fibronectin......; accumulation of fibronectin and alpha 1-alpha 2 type IV collagen on the endothelial face of the Descemet's membrane; and abnormal deposition of stromal ECM (tenascin, fibronectin, decorin, types I, III, V, VI, VIII, XII, XIV collagen) and BM components (type IV, collagen, perlecan, bamacan, laminin-1, entactin...

  11. ANALYSIS OF DONOR CORNEA RETRIEVAL DATA- HOSPITAL AND RESIDENCES

    Directory of Open Access Journals (Sweden)

    Rekha Gyanchand

    2017-07-01

    Full Text Available BACKGROUND The voluntary eye donation is still the most popular methods of eye donation in our country. Since last three decades, the voluntary eye donation is promoted by a number of NGOs and Government of India. The meaning of voluntary eye donation is that an individual has prior knowledge about eye donation and also has the contact number of the eye bank. When they come across any death in their community, they will contact the eye bank for eye donation. As per Eye Bank Association of India, the incidence of total blindness is 8.9 million and 1% of this is corneal blindness. Each year, 25,000 to 30,000/new corneal blind patients are added. The voluntary eye donation is not sufficient in providing transplantable corneas to the corneal blind. As our concentration is mainly on voluntary eye collections, this is one of the main reasons that we are unable reach our target of sight restoration in the management of corneal blindness. In this study, we have analysed the voluntary eye donations procured from residence and hospital. The aim of the study is to compare corneas procured by hospital eye donations and residence eye donations to look into all factors that contribute to a transplantable cornea. MATERIALS AND METHODS The donor corneas retrieved from the year 2005-2010 were analysed. The hospital eye donations and residential eye donations were divided into two study groups. The factors analysed were number of corneas collected, donor age and gender, serology test result, death to preservation time (DPT, optical grade cornea, utilisation of corneas for transplantation and role of pledging in eye donation. Study Type- Retrospective study. Study Done- At Lions International Eye Bank, Bangalore. RESULTS The total number of donor eyes collected from the year 2005-2010 were 7362 of which residence collections was 50.73% and hospital collections was 49.26%. The 5-year period between from 2005 to 2010 in spite of not conducting a Hospital Cornea

  12. [Riboflavin photoprotection with cross-linking effect in photorefractive ablation of the cornea].

    Science.gov (United States)

    Kornilovskiy, I M; Sultanova, A I; Burtsev, A A

    2016-01-01

    Photorefractive ablation is inevitably accompanied by oxidative stress of the cornea and weakening of its biomechanical and photoprotective properties. To validate the expediency of riboflavin use in photorefractive ablation for photoprotection of the cornea and cross-linking. The effects of riboflavin use in photorefractive ablation was first studied in a series of in vitro and in vivo experiments performed on 56 eyes of 28 rabbits, and then on 232 eyes of 142 patients with different degrees of myopia. Biomechanical testing of corneal samples was performed with Zwick/RoellВZ 2.5/TN1S tensile-testing machine. Transepithelial photorefractive keratectomy (TransPRK) and femtosecond laser-assisted in situ keratomileusis (Femto-LASIK) were performed on Wavelight-Allegretto200, MEL-80, and WaveLight-EX500 excimer laser systems and also VisuMax and WaveLight-FS200 femtosecond lasers. For preliminary examinations, an appropriate set of diagnostic tools was used. In vivo experiments have proved that, in the absence of conservative therapy, riboflavin is able to produce both photoprotective and cross-linking effects to the cornea. Corneal syndrome was thus reduced and re-epithelialization after TransPRK accelerated. Biomechanical testing of corneal samples revealed an increase in tolerated load from 12.9±1.4 N to 18.3±1.2 N (p=0.0002) and tensile strength from 8.6±1.7 MPa to 12.4±1.7 MPa (p=0.007). Clinical studies conducted in a group of patients with mild to moderate myopia have also confirmed the photoprotective effect of riboflavin at months 1-12 after TransPRK. There were no significant differences in uncorrected visual acuity (ranged from 0.80±0.16 to 0.85±0.15) and corrected visual acuity at baseline (0.83±0.14). Evaluation of the optical and refractive effect achieved after Femto-LASIK with riboflavin photoprotection in the fellow eye has shown that this technique is not inferior to the traditional one as to its refractive accuracy, but provides better

  13. Endogenous Locus Reporter Assays.

    Science.gov (United States)

    Liu, Yaping; Hermes, Jeffrey; Li, Jing; Tudor, Matthew

    2018-01-01

    Reporter gene assays are widely used in high-throughput screening (HTS) to identify compounds that modulate gene expression. Traditionally a reporter gene assay is built by cloning an endogenous promoter sequence or synthetic response elements in the regulatory region of a reporter gene to monitor transcriptional activity of a specific biological process (exogenous reporter assay). In contrast, an endogenous locus reporter has a reporter gene inserted in the endogenous gene locus that allows the reporter gene to be expressed under the control of the same regulatory elements as the endogenous gene, thus more accurately reflecting the changes seen in the regulation of the actual gene. In this chapter, we introduce some of the considerations behind building a reporter gene assay for high-throughput compound screening and describe the methods we have utilized to establish 1536-well format endogenous locus reporter and exogenous reporter assays for the screening of compounds that modulate Myc pathway activity.

  14. Thermal lens measurements in the cornea.

    Science.gov (United States)

    Venkatesh, S; Guthrie, S; Cruickshank, F R; Bailey, R T; Foulds, W S; Lee, W R

    1985-02-01

    Q-switched pulses from a neodymium/YAG (yttrium-aluminium-garnet) laser were passed through corneal discs taken from the enucleated eyes of three baboons and four rabbits. The time course of heat dissipation following absorption of laser energy by the tissue was studied with the use of a second continuous wave laser beam acting as a probe. It was found that the absorption of each neodymium/YAG pulse created a transient divergent lens within the cornea as theoretical considerations predicted. The relaxation time that characterised the decay of this thermal lens for a 1/e laser beam diameter of 2.0 mm was found to be 2.3 +/- 0.1 s (mean +/- standard error for 12 separate groups of measurements). Our results show that Q-switched laser pulses passing through apparently unaffected transparent tissues can induce thermal lens effects which persist for several seconds. The optical transfer of each pulse in a stream will be identical only if enough time is left between pulses for the tissues to return to their initial state. Therefore, when such laser pulses sharply focused to perform high precision intraocular surgery are used, thermal lensing in the transparent ocular media must limit the rate at which pulses can be usefully delivered.

  15. Femtosecond lasers for microsurgery of cornea

    International Nuclear Information System (INIS)

    Vartapetov, Sergei K; Khudyakov, D V; Lapshin, Konstantin E; Obidin, Aleksei Z; Shcherbakov, Ivan A

    2012-01-01

    The review of femtosecond laser installations for medical applications is given and a new femtosecond ophthalmologic system for creation of a flap of corneal tissue during the LASIK operation is described. An all-fibre femtosecond laser emitting ∼400-fs pulses at 1067 nm is used. The pulse repetition rate can vary from 200 kHz up to 1 MHz. The output energy of the femtosecond system does not exceed 1 μJ. A specially developed objective with small spherical and chromatic aberrations is applied to focus laser radiation to an area of an eye cornea. The size of the focusing spot does not exceed 3 μm. To process the required area, scanning by a laser beam is applied with a speed no less than 5 m s -1 . At a stage of preliminary tests of the system, the Κ8 glass, organic PMMA glass and specially prepared agarose gels are used as a phantom of an eye. The femtosecond system is successfully clinically tested on a plenty of eyes of a pig and on several human eyes. The duration of the procedure of creation of a corneal flap does not exceed 20 s.

  16. Femtosecond lasers for microsurgery of cornea

    Energy Technology Data Exchange (ETDEWEB)

    Vartapetov, Sergei K; Khudyakov, D V; Lapshin, Konstantin E; Obidin, Aleksei Z; Shcherbakov, Ivan A

    2012-03-31

    The review of femtosecond laser installations for medical applications is given and a new femtosecond ophthalmologic system for creation of a flap of corneal tissue during the LASIK operation is described. An all-fibre femtosecond laser emitting {approx}400-fs pulses at 1067 nm is used. The pulse repetition rate can vary from 200 kHz up to 1 MHz. The output energy of the femtosecond system does not exceed 1 {mu}J. A specially developed objective with small spherical and chromatic aberrations is applied to focus laser radiation to an area of an eye cornea. The size of the focusing spot does not exceed 3 {mu}m. To process the required area, scanning by a laser beam is applied with a speed no less than 5 m s{sup -1}. At a stage of preliminary tests of the system, the {Kappa}8 glass, organic PMMA glass and specially prepared agarose gels are used as a phantom of an eye. The femtosecond system is successfully clinically tested on a plenty of eyes of a pig and on several human eyes. The duration of the procedure of creation of a corneal flap does not exceed 20 s.

  17. Collagen cross-linking in thin corneas

    Directory of Open Access Journals (Sweden)

    Prema Padmanabhan

    2013-01-01

    Full Text Available Collagen cross-linking (CXL has become the standard of care for progressive keratoconus, after numerous clinical studies have established its efficacy and safety in suitably selected eyes. The standard protocol is applicable in eyes which have a minimum corneal thickness of 400 μm after epithelial debridement. This prerequisite was stipulated to protect the corneal endothelium and intraocular tissues from the deleterious effect of ultraviolet-A (UVA radiation. However, patients with keratoconus often present with corneal thickness of less than 400 μm and could have otherwise benefited from this procedure. A few modifications of the standard procedure have been suggested to benefit these patients without a compromise in safety. Transepithelial cross-linking, pachymetry-guided epithelial debridement before cross-linking, and the use of hypoosmolar riboflavin are some of the techniques that have been attempted. Although clinical data is limited at the present time, these techniques are worth considering in patients with thin corneas. Further studies are needed to scientifically establish their efficacy and safety.

  18. Factors influencing the virological testing of cornea donors.

    Science.gov (United States)

    Röck, Tobias; Beck, Robert; Jürgens, Stefan; Bartz-Schmidt, Karl Ulrich; Bramkamp, Matthias; Thaler, Sebastian; Röck, Daniel

    2017-11-01

    To assess the influence of donor, environment, and logistical factors on the results of virological testing of blood samples from cornea donors.Data from 670 consecutive cornea donors were analyzed retrospectively. Logistic regression analysis was used to assess the influence of different factors on the results of virological testing of blood samples from cornea donors.The mean annual rate of donors with serology-reactive or not evaluable result was 14.8% (99 of 670) (range 11.9%-16.9%). The cause of donor death by cancer increased the risk of serology-reactive or not evaluable result (P = .0300). Prolonged time between death and post mortem blood removal was associated with a higher rate of serology-reactive or not evaluable result (P donors, sex, and donor age had no significant impact on the results of virological testing of blood samples from cornea donors.The cause of donor death by cancer and a prolonged time between death and post mortem blood removal seem to be mainly responsible for serology-reactive or not evaluable result of blood samples from cornea donors. The percentage of discarded corneas caused by serology-reactive or not evaluable result may be reduced by shortening the period of time between death and post mortem blood removal. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  19. The putative imprinted locus D15S9 within the common deletion region for the Prader-Willi and Angelman syndromes encodes two overlapping mRNAs transcribed from opposite strands

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, C.C.; Driscoll, D.J. [Univ. of Florida, Gainesville, FL (United States); Saitoh, S. [Case Western Reserve Univ., Cleveland, OH (United States)] [and others

    1994-09-01

    Prader-Willi syndrome is typically caused by a deletion of paternal 15q11-q13, or maternal uniparental disomy (UPD) of chromosome 15, while Angelman syndrome is caused by a maternal deletion or paternal UPD of the same region. Therefore, these two clinically distinct neurobehavioral syndromes result from differential expression of imprinted genes within 15q11-q13. A 3.1 kb cDNA, DN34, from the D15S9 locus within 15q11-q13 was isolated from a human fetal brain library. We showed previously that DN34 probe detects a DNA methylation imprint and therefore may represent a candidate imprinted gene. Isolation of genomic clones and DNA sequencing demonstrated that the gene segment encoding the partial cDNA DN34 was split by a 2 kb intron, but did not encode a substantial open reading frame (ORF). Preliminary analysis of expression by RT-PCR suggests that this gene is expressed in fetal but not in tested tissue types from the adult, and thus its imprinting status has not been possible to assess at present. Surprisingly, we found an ORF on the antisense strand of the DN34 cDNA. This ORF encodes a putative polypeptide of 505 amino acid residues containing a RING C{sub 3}HC{sub 4} zinc-finger motif and other features of nuclear proteins. Subsequent characterization of this gene, ZNF127, and a mouse homolog, demonstrated expression of 3.2 kb transcript from all tested fetal and adult tissues. Transcripts initiate from within a CpG-island, shown to be differentially methylated on parental alleles in the human. Interestingly, functional imprinting of the mouse homolog was subsequently demonstrated in an F{sub 1} cross by analyzing a VNTR polymorphism in the mRNA. The ZNF127 gene is intronless, has significant overlap with the DN34 gene on the antisense strand, and a 1 kb 3{prime} end within the 2 kb DN34 intron.

  20. Serologic Evaluation of Cornea Donors and Microbiologic Evaluation of Cornea Storage Media in an Eye Bank from Izmir, Turkey.

    Science.gov (United States)

    Palamar, Melis; Degirmenci, Cumali; Sertoz, Ruchan; Aydemir, Sohret; Egrilmez, Sait; Yagci, Ayse

    2017-12-01

    Our objective was to evaluate the serologic positivity of cornea donors and microbiologic positivity of cornea storage media at the Ege University Tissue and Cornea Bank, Izmir, Turkey. We retrospectively investigated the serologic blood sample and microbiological culture media analysis results of all cornea donors at Ege University Tissue and Cornea Bank between 2007 and 2015 with reference to age, sex, and cause of death of each donor. Mean age of the 955 deceased donors was 43.19 ± 15.89 years (range, 2-65 y). The mean postmortem time to blood sample removal and excision of the cornea tissue was 8.4 hours (range, 4-12 h). Serologic analyses showed that 855 donors (89.5%) were seronegative. The remaining donors were seropositive for hepatitis B (54 donors; 5.7%), human immunodeficiency (27 donors; 2.8%), hepatitis C (14 donors; 1.5%), and syphilis (5 donors; 0.5%) virus infections. Microbiologic analyses of the storage media were negative, with no microorganisms shown in 855 samples (89.5%). Candida species (32 donors; 3.4%), Escherichia coli (14 donors; 1.5%), Pseudomonas aeruginosa (11 donors; 1.2%), methicillin-resistant Staphylococcus aureus (11 donors; 1.2%), Enterobacter species (11 donors; 1.2%), Klebsiella pneumoniae (7 donors; 0.7%), Acinetobacter baumannii (6 donors; 0.6%), Proteus species (5 donors; 0.5%), and Corynebacterium species (3 donors; 0.3%) were the detected microorganisms in the infected storage media. False-positive serologic results among cornea donors were high. The incidence of false-positive results might be decreased by earlier blood removal from deceased donors and testing of all potential donors in intensive care units. Although rare, endophthalmitis after keratoplasty might be a devastating problem. In addition to serologic testing, microbiologic analyses of cornea storage media before transplant may be an effective way to prevent postoperative infectious complications.

  1. The IGF2 Locus

    Science.gov (United States)

    Insulin-like growth factor 2 (IGF2) is a peptide hormone regulating various cellular processes such as proliferation and apoptosis. IGF2 is vital to embryo development. The IGF2 locus covers approximately 150-kb genomic region on human chromosome 11, containing two imprinted genes, IGF2 and H19, sha...

  2. Matrix metalloproteinase expression in excimer laser wounded rabbit corneas

    Science.gov (United States)

    Hahn, Taewon; Chamon, Wallace; Akova, Yonja; Stark, Walter J.; Stetler-Stevenson, William G.; Azar, Dimitri T.

    1994-06-01

    This study was performed to obtain information about matrix metalloproteinase (MMP) expression in excimer-wounded corneas and to determine whether MMPs expression correlates with the depth of the ablation. 6-mm excimer keratectomy (60 or 180 micrometers ) was performed using the 193-mm ArF excimer laser on 12 NZW rabbits. Corneas treated with mechanical epithelial debridement and untreated corneas served as controls. Rabbits were killed at 20 and 30 hr after laser ablation. Zymography after SDS extraction was performed on regenerated central epithelium and the central stroma to determine MMPs expression. We observed enzymatic activity of a 92 KDa band in the epithelium of excimer-ablated corneas but not in that following debridement wounds and untreated controls. The expression of the 92 KDa MMP was most pronounced with the deeper excimer ablation. A 72 KDa band of enzymatic activity present in the stroma of all treated and control eyes was also seen in the epithelium of excimer-ablated corneas. These proteolytic enzymes may play an important role in wound healing and remodelling after excimer keratectomy.

  3. Analysis of Riboflavin Compounds in the Rabbit Cornea In Vivo.

    Science.gov (United States)

    Hammer, Arthur; Rudaz, Serge; Guinchard, Sylvie; Kling, Sabine; Richoz, Olivier; Hafezi, Farhad

    2016-09-01

    To investigate the composition and concentration of individual riboflavin compounds in the corneal stroma in vivo after soaking with various commercially available riboflavin formulations. Experiments were performed in 26 rabbit corneas in vivo: 24 corneas were soaked with riboflavin formulations for 30 minutes or with 0.9% NaCl for control (n = 2). After treatment, corneas were excised and prepared for ultra-high-pressure liquid chromatography (UHPLC) analysis. Additionally, computational chemical analysis of riboflavin compounds and keratan sulfate were performed. The amount of riboflavin and riboflavin phosphate isomers in cornea decreased by a factor of 10 to 100, when compared to the amount in riboflavin formulations. In particular, we found an inverse relationship in the ratio of riboflavin to riboflavin phosphate isomer concentration between formulations and cornea. The electronegativity and ionization potential of riboflavin and phosphate isomers are different. The inverse relationship observed might be explained by a stronger electronegativity of the phosphate isomers, leading to a stronger repulsion by corneal proteoglycans. Indicating the individual concentration of riboflavin compounds in formulations is more representative than the total riboflavin concentration. Riboflavin formulations and CXL protocols might be improved considering the differences in diffusion and ionization potentials of the different riboflavin compounds.

  4. A locus for isolated cataract on human Xp.

    Science.gov (United States)

    Francis, P J; Berry, V; Hardcastle, A J; Maher, E R; Moore, A T; Bhattacharya, S S

    2002-02-01

    To genetically map the gene causing isolated X linked cataract in a large European pedigree. Using the patient registers at Birmingham Women's Hospital, UK, we identified and examined 23 members of a four generation family with nuclear cataract. Four of six affected males also had complex congenital heart disease. Pedigree data were collated and leucocyte DNA extracted from venous blood. Linkage analysis by PCR based microsatellite marker genotyping was used to identify the disease locus and mutations within candidate genes screened by direct sequencing. The disease locus was genetically refined to chromosome Xp22, within a 3 cM linkage interval flanked by markers DXS9902 and DXS999 (Zmax=3.64 at theta=0 for marker DXS8036). This is the first report of a locus for isolated inherited cataract on the X chromosome. The disease interval lies within the Nance-Horan locus suggesting allelic heterogeneity. The apparent association with congenital cardiac anomalies suggests a possible new oculocardiac syndrome.

  5. In vitro confocal imaging of the rabbit cornea.

    Science.gov (United States)

    Masters, B R; Paddock, S

    1990-05-01

    We were able to observe in vitro the fine structure of the rabbit cornea using a laser scanning confocal microscope, especially in the regions between Descemet's membrane and the epithelial basal lamina. We observed submicrometre filaments throughout the stroma with high concentrations adjacent to Descemet's membrane, and found extensive interconnecting processes between stromal keratocytes. There are numerous regions containing nerve plexuses in the stroma. We found a deeply convoluted basal lamina adjacent to the epithelium, and observed regions containing junctions between endothelial cells in fluorescent images of rabbit corneas stained with the actin-specific compound fluorescein phalloidin.

  6. LEOPARD syndrome is not linked to the Marfan syndrome and the Watson syndrome loci

    Energy Technology Data Exchange (ETDEWEB)

    Rass-Rothchild, A.: Abeliovitch, D.; Kornstein, A. [Tel Aviv Univ. (Israel)]|[Hebrew Univ., Jerusalem (Israel)

    1994-09-01

    The acronym LEOPARD stands for a syndromic association of Lentigines, Eletrocardiographic changes, Ocular hypertelorism, Pulmonic stenosis, Abnormal genitalia, Retardation of growth and sensorineural Deafness. Inheritance is autosomal dominant with high penetrance and variable expressivity. In 1990 Torok et al. reported on the association of LEOPARD and Marfan syndrome. In addition a clinical similarity (cardiac and cutaneous involvement) exists with the Watson syndrome (neurofibromatosis and pulmonic stenosis) which is linked to the marker D17S33 on chromosome 17. We studied possible linkage of LEOPARD syndrome to the Marfan syndrome locus on chromosome 15 (D15S1, MF13, and (TAAAA)n repeats) and to the NF-1 locus on chromosome 17 in a family with 9 cases of LEOPARD syndrome. Close linkage between LEOPARD syndrome and both the Marfan locus on chromosome 15 and the NF-1 locus on chromosome 17 was excluded (lod score <-2.0 through {theta} = 0.1).

  7. File list: ALL.Oth.50.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.50.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX437636,SRX24830...2,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.50.AllAg.Cornea.bed ...

  8. File list: ALL.Oth.05.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.05.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX437636,SRX24830...2,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.05.AllAg.Cornea.bed ...

  9. File list: ALL.Oth.20.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.20.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX437636,SRX24830...2,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.20.AllAg.Cornea.bed ...

  10. File list: ALL.Oth.10.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.10.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX248302,SRX43763...6,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.10.AllAg.Cornea.bed ...

  11. Thick keratoconic cornea associated with posterior polymorphous corneal dystrophy.

    Science.gov (United States)

    Zaarour, K; Slim, E; Antoun, J; Waked, N

    2017-03-01

    We herein report a case of bilateral unusually thick non-edematous keratoconic corneas with associated endothelial features of posterior polymorphous corneal dystrophy (PPCD). We report the case of a 27-year-old myopic woman who presented for refractive surgery. Slit lamp exam showed bilateral corneal protrusion with diffuse deep stromal and endothelial vesicular opacities and small paracentral bands. Topography showed generalized advanced corneal steepening in both eyes with increased anterior and posterior central corneal elevations in comparison to the best fit sphere. Ultrasound pachymetry showed central corneal thickness of 605μm (RE) and 612μm (LE). On specular biomicroscopy, cell density of 2503 cells/mm 2 RE and 1526 cells/mm 2 LE with significant cellular pleomorphism and polymegathism were noted. Clinical and paraclinical findings together suggest the presence of simultaneous keratoconus and PPCD. The literature has suggested an association between PPCD and steep cornea. Moreover, many reports have also described cases of associated PPCD and keratoconus with characteristic thinning and ectasia, in comparison to the unusual thick corneas noted in our patient, despite the absence of edema. Identification of genetics factors is further needed to clarify this association. This case describes a patient whose corneas present features of both keratoconus and PPCD and is unique due to the presence of increased corneal thickness despite the absence of edema. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  12. Mesothelial proteins are expressed in the human cornea

    Czech Academy of Sciences Publication Activity Database

    Jirsová, K.; Neuwirth, Aleš; Kalašová, S.; Veselá, V.; Merjava, S.

    2010-01-01

    Roč. 91, č. 5 (2010), s. 623-629 ISSN 0014-4835 Institutional research plan: CEZ:AV0Z50520514 Keywords : cornea * HBME-1 (Hector Battifora mesothelial cell-1) protein * calbindin 2 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.817, year: 2010

  13. Correlation between epithelial thickness in normal corneas, untreated ectatic corneas, and ectatic corneas previously treated with CXL; is overall epithelial thickness a very early ectasia prognostic factor?

    Directory of Open Access Journals (Sweden)

    Kanellopoulos AJ

    2012-05-01

    Full Text Available Anastasios John Kanellopoulos,1,2 Ioannis M Aslanides,3 George Asimellis11Laservision Eye Institute, Athens, 2Emmetropia Mediterranean Eye Clinic, Crete, Greece, 3New York University School of Medicine, NY, USAPurpose: To determine and correlate epithelial corneal thickness (pachymetric measurements taken with a digital arc scanning very high frequency ultrasound biomicroscopy (HF UBM imaging system (Artemis-II, and compare mean and central epithelial thickness among normal eyes, untreated keratoconic eyes, and keratoconic eyes previously treated with collagen crosslinking (CXL.Methods: Epithelial pachymetry measurements (topographic mapping were conducted on 100 subjects via HF UBM. Three groups of patients were included: patients with normal eyes (controls, patients with untreated keratoconic eyes, and patients with keratoconic eyes treated with CXL. Central, mean, and peripheral corneal epithelial thickness was examined for each group, and a statistical study was conducted.Results: Mean, central, and peripheral corneal epithelial thickness was compared between the three groups of patients. Epithelium thickness varied substantially in the keratoconic group, and in some cases there was a difference of up to 20 µm between various points of the same eye, and often a thinner epithelium coincided with a thinner cornea. However, on average, data from the keratoconic group suggested an overall thickening of the epithelium, particularly over the pupil center of the order of +3 µm, while the mean epithelium thickness was on average +1.1 µm, compared to the control population (P = 0.005. This overall thickening was more pronounced in younger patients in the keratoconic group. Keratoconic eyes previously treated with CXL showed, on average, virtually the same average epithelium thickness (mean –0.7 µm, –0.2 µm over the pupil center, –0.9 µm over the peripheral zone as the control group. This finding further reinforces our novel theory of the

  14. A Mouse Model of the Cornea Pocket Assay for Angiogenesis Study

    Science.gov (United States)

    Tang, Zhongshu; Zhang, Fan; Li, Yang; Arjunan, Pachiappan; Kumar, Anil; Lee, Chunsik; Li, Xuri

    2011-01-01

    A normal cornea is clear of vascular tissues. However, blood vessels can be induced to grow and survive in the cornea when potent angiogenic factors are administered 1. This uniqueness has made the cornea pocket assay one of the most used models for angiogenesis studies. The cornea composes multiple layers of cells. It is therefore possible to embed a pellet containing the angiogenic factor of interest in the cornea to investigate its angiogenic effect 2,3. Here, we provide a step by step demonstration of how to (I) produce the angiogenic factor-containing pellet (II) embed the pellet into the cornea (III) analyze the angiogenesis induced by the angiogenic factor of interest. Since the basic fibroblast growth factor (bFGF) is known as one of the most potent angiogenic factors 4, it is used here to induce angiogenesis in the cornea. PMID:21876523

  15. Correlation between epithelial thickness in normal corneas, untreated ectatic corneas, and ectatic corneas previously treated with CXL; is overall epithelial thickness a very early ectasia prognostic factor?

    Science.gov (United States)

    Kanellopoulos, Anastasios John; Aslanides, Ioannis M; Asimellis, George

    2012-01-01

    To determine and correlate epithelial corneal thickness (pachymetric) measurements taken with a digital arc scanning very high frequency ultrasound biomicroscopy (HF UBM) imaging system (Artemis-II), and compare mean and central epithelial thickness among normal eyes, untreated keratoconic eyes, and keratoconic eyes previously treated with collagen crosslinking (CXL). Epithelial pachymetry measurements (topographic mapping) were conducted on 100 subjects via HF UBM. Three groups of patients were included: patients with normal eyes (controls), patients with untreated keratoconic eyes, and patients with keratoconic eyes treated with CXL. Central, mean, and peripheral corneal epithelial thickness was examined for each group, and a statistical study was conducted. Mean, central, and peripheral corneal epithelial thickness was compared between the three groups of patients. Epithelium thickness varied substantially in the keratoconic group, and in some cases there was a difference of up to 20 μm between various points of the same eye, and often a thinner epithelium coincided with a thinner cornea. However, on average, data from the keratoconic group suggested an overall thickening of the epithelium, particularly over the pupil center of the order of +3 μm, while the mean epithelium thickness was on average +1.1 μm, compared to the control population (P = 0.005). This overall thickening was more pronounced in younger patients in the keratoconic group. Keratoconic eyes previously treated with CXL showed, on average, virtually the same average epithelium thickness (mean -0.7 μm, -0.2 μm over the pupil center, -0.9 μm over the peripheral zone) as the control group. This finding further reinforces our novel theory of the "reactive" component of epithelial thickening in corneas that are biomechanically unstable, becoming stable when biomechanical rigidity is accomplished despite persistence of cornea topographic irregularity. A highly irregular epithelium may be

  16. Why Does the Healthy Cornea Resist Pseudomonas aeruginosa Infection?

    Science.gov (United States)

    Evans, David J.; Fleiszig, Suzanne M. J.

    2013-01-01

    Purpose To provide our perspective on why the cornea is resistant to infection based on our research results with Pseudomonas aeruginosa. Perspective We focus on our current understanding of the interplay between bacteria, tear fluid and the corneal epithelium that determine health as the usual outcome, and propose a theoretical model for how contact lens wear might change those interactions to enable susceptibility to P. aeruginosa infection. Methods Use of “null-infection” in vivo models, cultured human corneal epithelial cells, contact lens-wearing animal models, and bacterial genetics help to elucidate mechanisms by which P. aeruginosa survive at the ocular surface, adheres, and traverses multilayered corneal epithelia. These models also help elucidate the molecular mechanisms of corneal epithelial innate defense. Results and Discussion Tear fluid and the corneal epithelium combine to make a formidable defense against P. aeruginosa infection of the cornea. Part of that defense involves the expression of antimicrobials such as β-defensins, the cathelicidin LL-37, cytokeratin-derived antimicrobial peptides, and RNase7. Immunomodulators such as SP-D and ST2 also contribute. Innate defenses of the cornea depend in part on MyD88, a key adaptor protein of TLR and IL-1R signaling, but the basal lamina represents the final barrier to bacterial penetration. Overcoming these defenses involves P. aeruginosa adaptation, expression of the type three secretion system, proteases, and P. aeruginosa biofilm formation on contact lenses. Conclusion After more than two decades of research focused on understanding how contact lens wear predisposes to P. aeruginosa infection, our working hypothesis places blame for microbial keratitis on bacterial adaptation to ocular surface defenses, combined with changes to the biochemistry of the corneal surface caused by trapping bacteria and tear fluid against the cornea under the lens. PMID:23601656

  17. In vivo confocal Raman spectroscopy of the human cornea.

    Science.gov (United States)

    Bauer, N J; Hendrikse, F; March, W F

    1999-07-01

    To investigate the feasibility of a confocal Raman spectroscopic technique for the noninvasive assessment of corneal hydration in vivo in two legally blind subjects. A laser beam (632.8 nm; 15 mJ) was maintained on the cornea by using a microscope objective lens (x25 magnification, NA = 0.5, f = 10 mm) both for focusing the incident light as well as collecting the Raman backscattered light, in a 180 degrees backscatter configuration. An optical fiber, acting as the confocal pinhole for elimination of light from out-of-focus places, was coupled to a spectrometer that dispersed the collected light onto a sensitive array detector for rapid spectral data acquisition over a range from 2,890 to 3,590/cm(-1). Raman spectra were recorded from the anterior 100-150 microm of the cornea over a period before and after topical application of a mild dehydrating solution. The ratio between the amplitudes of the signals at 3,400/cm(-1) (OH-vibrational mode of water) and 2,940/cm(-1) (CH-vibrational mode of proteins) was used as a measure for corneal hydration. High signal-to-noise ratio (SNR = 25) Raman spectra were obtained from the human corneas by using 15 mJ of laser light energy. Qualitative changes in the hydration of the anteriormost part of the corneas could be observed as a result of the dehydrating agent. With adequate improvements in system safety, confocal Raman spectroscopy could potentially be applied clinically as a noninvasive tool for the assessment of corneal hydration in vivo.

  18. Effects of genipin corneal crosslinking in rabbit corneas.

    Science.gov (United States)

    Avila, Marcel Y; Narvaez, Mauricio; Castañeda, Juan P

    2016-07-01

    To evaluate the effect of genipin, a natural crosslinking agent, in rabbit eyes. Department of Ophthalmology, Universidad Nacional de Colombia Centro de Tecnologia Oftalmica, Bogotá, Colombia. Experimental study. Ex vivo rabbit eyes (16; 8 rabbits) were treated with genipin 1.00%, 0.50%, and 0.25% for 5 minutes with a vacuum device to increase corneal permeability. Penetration was evaluated using Scheimpflug pachymetry (Pentacam). In the in vivo model (20 rabbits; 1 eye treated, 1 eye with vehicle), corneas were crosslinked with genipin as described. Corneal curvature, corneal pachymetry, and intraocular pressure (IOP) assessments as well as slitlamp examinations were performed 0, 7, 30, and 60 days after treatment. In the ex vivo model, Scheimpflug pachymetry showed deep penetration in the rabbit corneas with an increase in corneal density and a dose-dependent relationship. Corneal flattening was observed in treated eyes (mean 4.4 diopters ± 0.5 [SD]) compared with the control eyes. Pachymetry and IOP were stable in all evaluations. No eye showed toxicity in the anterior chamber or in the lens. Corneal crosslinking induced by genipin produced significant flattening of the cornea with no toxicity in rabbit eyes. This crosslinking could be useful in the treatment of corneal ectasia and in the modification of corneal curvature. None of the authors has a financial or proprietary interest in any material or method mentioned. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  19. Computational modeling of drug transport across the in vitro cornea.

    Science.gov (United States)

    Pak, Joseph; Chen, Z J; Sun, Kay; Przekwas, Andrzej; Walenga, Ross; Fan, Jianghong

    2018-01-01

    A novel quasi-3D (Q3D) modeling approach was developed to model networks of one dimensional structures like tubes and vessels common in human anatomy such as vascular and lymphatic systems, neural networks, and respiratory airways. Instead of a branching network of the same tissue type, this approach was extended to model an interconnected stack of different corneal tissue layers with membrane junction conditions assigned between the tissues. The multi-laminate structure of the cornea presents a unique barrier design and opportunity for investigation using Q3D modeling. A Q3D model of an in vitro rabbit cornea was created to simulate the drug transport across the cornea, accounting for transcellular and paracellular pathways of passive and convective drug transport as well as physicochemistry of lipophilic partitioning and protein binding. Lipophilic Rhodamine B and hydrophilic fluorescein were used as drug analogs. The model predictions for both hydrophilic and lipophilic tracers were able to match the experimental measurements along with the sharp discontinuities at the epithelium-stroma and stroma-endothelium interfaces. This new modeling approach was successfully applied towards pharmacokinetic modeling for use in topical ophthalmic drug design. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Clinical and epidemiological aspects of cornea transplant patients of a reference hospital 1

    Science.gov (United States)

    Cruz, Giovanna Karinny Pereira; de Azevedo, Isabelle Campos; Carvalho, Diana Paula de Souza Rego Pinto; Vitor, Allyne Fortes; Santos, Viviane Euzébia Pereira; Ferreira, Marcos Antonio

    2017-01-01

    ABSTRACT Objective: clinically characterizing cornea transplant patients and their distribution according to indicated and post-operative conditions of cornea transplantation, as well as estimating the average waiting time. Method: a cross-sectional, descriptive and analytical study performed for all cornea transplants performed at a reference service (n=258). Data were analyzed using Statistical Package for the Social Sciences, version 20.0. Results: the main indicator for cornea transplant was keratoconus. The mean waiting time for the transplant was approximately 5 months and 3 weeks for elective transplants and 9 days for urgent cases. An association between the type of corneal disorder with gender, age, previous surgery, eye classification, glaucoma and anterior graft failure were found. Conclusion: keratoconus was the main indicator for cornea transplant. Factors such as age, previous corneal graft failure (retransplantation), glaucoma, cases of surgeries prior to cornea transplant (especially cataract surgery) may be related to the onset corneal endothelium disorders. PMID:28614429

  1. Cytogenetic damage and postradiation restoration of eye cornea epithelium of Rodentia characterizing by different radiosensitivity

    International Nuclear Information System (INIS)

    Popova, M.F.; Bulyakova, N.V.

    1983-01-01

    Intensity of beam damage and reparation of eye cornea epithelium of animals inhabiting under different conditions and differing by radiosensitivity has been studied. Mice differing by high radiosensitivity have the hardest cytogenetic damage. Cornea epithelium of bank voles is more radiostable than that of mice. The most negligible damages of cornea epithelium is observed in Mongolian sandwort despite the fact that their total radiation stability is lower than that of bank voles. High protective-restoring properties of eye cornea epithelium of Mongolian sandwort are explained by the structure of epithelium cells diffe-- ring by a large number of cytoplasm

  2. Experimental corneal calcification, hydration and /sup 45/Ca uptake in rabbit corneas incubated in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Obenberger, J [Ceskoslovenska Akademie Ved, Prague. Oftalmologicka Laborator; Dobiasova, M; Babicky, A [Ceskoslovenska Akademie Ved, Prague. Isotopova Laborator Biologickych Ustavu

    1974-07-01

    Experimental corneal calcification could easily be produced by a combination of corneal injury (perfusion of the anterior chamber of the eye with a solution of potassium permanganate) amd dihydrotachysterol (DHT) treatment. Rabbit corneas with induced calcification as well as corneas of three additional groups of rabbits, i.e. those treated with permanganate or DHT only and control animals were incubated for two hours in a medium containing /sup 45/Ca. An increased uptake of /sup 45/Ca into the cornea was found in the group of rabbits receiving DHT only. Potassium cyanide added to the incubation medium did not affect corneal hydration nor the final activity of the incubated corneas. (auth)

  3. Second harmonic generation microscopy of the living human cornea

    Science.gov (United States)

    Artal, Pablo; Ávila, Francisco; Bueno, Juan

    2018-02-01

    Second Harmonic Generation (SHG) microscopy provides high-resolution structural imaging of the corneal stroma without the need of labelling techniques. This powerful tool has never been applied to living human eyes so far. Here, we present a new compact SHG microscope specifically developed to image the structural organization of the corneal lamellae in living healthy human volunteers. The research prototype incorporates a long-working distance dry objective that allows non-contact three-dimensional SHG imaging of the cornea. Safety assessment and effectiveness of the system were firstly tested in ex-vivo fresh eyes. The maximum average power of the used illumination laser was 20 mW, more than 10 times below the maximum permissible exposure (according to ANSI Z136.1-2000). The instrument was successfully employed to obtain non-contact and non-invasive SHG of the living human eye within well-established light safety limits. This represents the first recording of in vivo SHG images of the human cornea using a compact multiphoton microscope. This might become an important tool in Ophthalmology for early diagnosis and tracking ocular pathologies.

  4. Visual acuity outcomes in eyes with flat corneas after PRK.

    Science.gov (United States)

    Varssano, David; Waisbourd, Michael; Minkev, Liza; Sela, Tzahi; Neudorfer, Meira; Binder, Perry S

    2013-06-01

    To evaluate the impact of corneal curvatures less than 35 diopters (D) after photorefractive keratectomy (PRK) on visual acuity outcomes. Visual acuity outcomes of 5,410 eyes that underwent PRK from January 2006 to November 2010 were retrospectively analyzed for the impact of postoperative corneal curvatures on visual outcomes. All procedures were performed on a single platform (Allegretto 200Hz excimer laser; Alcon Laboratories, Inc., Irvine, CA). Main outcome measures were postoperative corrected distance visual acuity (CDVA) and loss of CDVA. Corneas with a measured or a calculated postoperative flat meridian less than 35 D and those with a measured postoperative steep meridian less than 35 D had worse postoperative CDVA than corneas with meridians of either 35 D or more (P ≤ .021). However, the preoperative CDVA was worse in the flatter curvatures in all comparisons performed (P ≤ .024). Consequently, the measured or calculated meridian curvature had no effect on CDVA loss (P ≥ .074). Postoperative corneal keratometry values (flat and steep meridians) less than 35 D did not have a predictive effect on the risk of losing visual acuity following myopic PRK performed on the Allegretto 200Hz excimer laser. Copyright 2013, SLACK Incorporated.

  5. Use of Fourier-Domain Optical Coherence Tomography to Evaluate Anterior Stromal Opacities in Donor Corneas

    Directory of Open Access Journals (Sweden)

    Matthew R. Bald

    2013-01-01

    Full Text Available Purpose. To evaluate Fourier-domain optical coherence tomography (FD-OCT as an adjunct to traditional slit lamp examination of donor corneas with suspected Anterior Stromal Opacities. Methods. Seven corneas suspected of having anterior stromal opacities by slit lamp examination were evaluated with FD-OCT. Each cornea was evaluated to confirm the presence of opacity and, if present, the depth of opacity was measured. Results. The opacity depth ranged from 82 μm to 624 μm. The initial slit lamp impressions of five of the seven corneas were confirmed by OCT. In two corneas, the OCT findings were different from the initial slit lamp impressions. Slit lamp examination of the first cornea gave the impression of anterior stromal scarring, but OCT showed that the opacity was limited to the epithelium. Slit lamp examination of the second cornea suggested opacity limited to the epithelium, but OCT identified significant sub-Bowman's scarring. In all cases, the Eye Bank Technicians reported that the location and depth of corneal opacity were more sharply defined by OCT than by slit lamp. Conclusion. The high resolution of OCT makes it easier to determine the location of corneal opacities compared to slit lamp examinations. This enhanced visualization can improve decisions regarding transplant suitability of donor corneas.

  6. Xanthelasmata, arcus corneae, and ischaemic vascular disease and death in general population: prospective cohort study

    DEFF Research Database (Denmark)

    Christoffersen, Mette; Frikke-Schmidt, Ruth; Schnohr, Peter

    2011-01-01

    To test the hypothesis that xanthelasmata and arcus corneae, individually and combined, predict risk of ischaemic vascular disease and death in the general population.......To test the hypothesis that xanthelasmata and arcus corneae, individually and combined, predict risk of ischaemic vascular disease and death in the general population....

  7. Comparison of confocal microscopy and two-photon microscopy in mouse cornea in vivo.

    Science.gov (United States)

    Lee, Jun Ho; Lee, Seunghun; Gho, Yong Song; Song, In Seok; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2015-03-01

    High-resolution imaging of the cornea is important for studying corneal diseases at cellular levels. Confocal microscopy (CM) has been widely used in the clinic, and two-photon microscopy (TPM) has recently been introduced in various pre-clinical studies. We compared the performance of CM and TPM in normal mouse corneas and neovascularized mouse corneas induced by suturing. Balb/C mice and C57BL/6 mice expressing green fluorescent protein (GFP) were used to compare modalities based on intrinsic contrast and extrinsic fluorescence contrast. CM based on reflection (CMR), CM based on fluorescence (CMF), and TPM based on intrinsic/extrinsic fluorescence and second harmonic generation (SHG) were compared by imaging the same sections of mouse corneas sequentially in vivo. In normal mouse corneas, CMR visualized corneal cell morphologies with some background noise, and CMF visualized GFP expressing corneal cells clearly. TPM visualized corneal cells and collagen in the stroma based on fluorescence and SHG, respectively. However, in neovascularized mouse corneas, CMR could not resolve cells deep inside the cornea due to high background noise from the effects of increased structural irregularity induced by suturing. CMF and TPM visualized cells and induced vasculature better than CMR because both collect signals from fluorescent cells only. Both CMF and TPM had signal decays with depth due to the structural irregularity, with CMF having faster signal decay than TPM. CMR, CMF, and TPM showed different degrees of image degradation in neovascularized mouse corneas. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Locus of Control and Obesity

    Directory of Open Access Journals (Sweden)

    Florence eNeymotin

    2014-10-01

    Full Text Available In the developed world, the hazards associated with obesity have largely outstripped the risk of starvation. Obesity remains a difficult public health issue to address, due in large part to the many disciplines involved. A full understanding requires knowledge in the fields of genetics, endocrinology, psychology, sociology, economics, and public policy – among others. In this short review, which serves as an introduction to the Frontiers in Endocrinology research topic, we address one cross-disciplinary relationship: the interaction between the hunger/satiation neural circuitry, an individual’s perceived locus of control, and the risk for obesity. Mammals have evolved a complex system for modulating energy intake. Overlaid on this, in humans, there exists a wide variation in perceived locus of control – that is, the extent to which an individual believes to be in charge of the events that affect them. Whether one has primarily an internal or external locus of control itself affects, and is affected by, external and physiological factors and has been correlated with the risk for obesity. Thus, the path from hunger and satiation to an individual’s actual behavior may often be moderated by psychological factors, included among which is locus of control.

  9. Locus of control and obesity.

    Science.gov (United States)

    Neymotin, Florence; Nemzer, Louis R

    2014-01-01

    In the developed world, the hazards associated with obesity have largely outstripped the risk of starvation. Obesity remains a difficult public health issue to address, due in large part to the many disciplines involved. A full understanding requires knowledge in the fields of genetics, endocrinology, psychology, sociology, economics, and public policy - among others. In this short review, which serves as an introduction to the Frontiers in Endocrinology research topic, we address one cross-disciplinary relationship: the interaction between the hunger/satiation neural circuitry, an individual's perceived locus of control, and the risk for obesity. Mammals have evolved a complex system for modulating energy intake. Overlaid on this, in humans, there exists a wide variation in "perceived locus of control" - that is, the extent to which an individual believes to be in charge of the events that affect them. Whether one has primarily an internal or external locus of control itself affects, and is affected by, external and physiological factors and has been correlated with the risk for obesity. Thus, the path from hunger and satiation to an individual's actual behavior may often be moderated by psychological factors, included among which is locus of control.

  10. Congenital hereditary endothelial dystrophy with progressive sensorineural deafness (Harboyan syndrome

    Directory of Open Access Journals (Sweden)

    Abramowicz Marc

    2008-10-01

    Full Text Available Abstract Harboyan syndrome is a degenerative corneal disorder defined as congenital hereditary endothelial dystrophy (CHED accompanied by progressive, postlingual sensorineural hearing loss. To date, 24 cases from 11 families of various origin (Asian Indian, South American Indian, Sephardi Jewish, Brazilian Portuguese, Dutch, Gypsy, Moroccan, Dominican have been reported. More than 50% of the reported cases have been associated with parental consanguinity. The ocular manifestations in Harboyan syndrome include diffuse bilateral corneal edema occurring with severe corneal clouding, blurred vision, visual loss and nystagmus. They are apparent at birth or within the neonatal period and are indistinguishable from those characteristic of the autosomal recessive CHED (CHED2. Hearing deficit in Harboyan is slowly progressive and typically found in patients 10–25 years old. There are no reported cases with prelinglual deafness, however, a significant hearing loss in children as young as 4 years old has been detected by audiometry, suggesting that hearing may be affected earlier, even at birth. Harboyan syndrome is caused by mutations in the SLC4A11 gene located at the CHED2 locus on chromosome 20p13-p12, indicating that CHED2 and Harboyan syndrome are allelic disorders. A total of 62 different SLC4A11 mutations have been reported in 98 families (92 CHED2 and 6 Harboyan. All reported cases have been consistent with autosomal recessive transmission. Diagnosis is based on clinical criteria, detailed ophthalmological assessment and audiometry. A molecular confirmation of the clinical diagnosis is feasible. A variety of genetic, metabolic, developmental and acquired diseases presenting with clouding of the cornea should be considered in the differential diagnosis (Peters anomaly, sclerocornea, limbal dermoids, congenital glaucoma. Audiometry must be performed to differentiate Harboyan syndrome from CHED2. Autosomal recessive types of CHED (CHED2 and

  11. Tissue Engineering the Cornea: The Evolution of RAFT

    Science.gov (United States)

    Levis, Hannah J.; Kureshi, Alvena K.; Massie, Isobel; Morgan, Louise; Vernon, Amanda J.; Daniels, Julie T.

    2015-01-01

    Corneal blindness affects over 10 million people worldwide and current treatment strategies often involve replacement of the defective layer with healthy tissue. Due to a worldwide donor cornea shortage and the absence of suitable biological scaffolds, recent research has focused on the development of tissue engineering techniques to create alternative therapies. This review will detail how we have refined the simple engineering technique of plastic compression of collagen to a process we now call Real Architecture for 3D Tissues (RAFT). The RAFT production process has been standardised, and steps have been taken to consider Good Manufacturing Practice compliance. The evolution of this process has allowed us to create biomimetic epithelial and endothelial tissue equivalents suitable for transplantation and ideal for studying cell-cell interactions in vitro. PMID:25809689

  12. The effects of oral and topical corticosteroid in rabbit corneas.

    Science.gov (United States)

    Araki-Sasaki, Kaoru; Katsuta, Osamu; Mano, Hidetoshi; Nagano, Takashi; Nakamura, Masatsugu

    2016-09-05

    To determine the most effective route of administration of corticosteroids in the treatment of ocular surface disease, by characterizing the difference between oral prednisolone and topical dexamethasone administration using an animal model. Pharmacokinetic analyses determined the corticosteroid concentrations in the normal ocular tissues of rabbits after oral or topical administration of corticosteroids using LC-MS/MS. In wound healing analyses, the area of the epithelial defect created by keratectomy using a 6-mm trephine was calculated with an image analyzer using an orally or topically steroid-administrated animal model. The average size of basal epithelial cells, the frequency of mitotic basal epithelial cells, the number of squamous cells, and the number of hypertrophic stromal fibroblasts were determined in the enucleated corneal tissues after wound closure. By slit lamp examination, no remarkable differences were observed between orally and topically administered groups. Pharmacokinetic analyses showed that the distribution of dexamethasone after topical administration was superior to that after oral administration in the cornea. In contrast, both concentrations of corticosteroid applied topically and orally were similar with regards to AUCs (area under the concentration-time curve) in the conjunctiva. Although the healing rate was slower in the topical group, all corneas were almost healed within 96 h in the wound healing analysis. According to the histological analyses of epithelial cells, the average basal cell size was larger, the frequency of mitotic basal cells was greater, and the number of squamous epithelial cell layers was lower in the topically administered group although all of these differences were with no statistical significance. However, the number of hypertrophic stromal fibroblasts in the topically administered group was significantly lower than that in the orally administered group. There are different distributions and effects between

  13. Xanthelasma palpebrarum with arcus cornea: A clinical and biochemical study

    Directory of Open Access Journals (Sweden)

    Pragya Ashok Nair

    2016-01-01

    Full Text Available Background: Xanthelasma palpebrarum (XP is characterized by sharply demarcated yellowish flat plaques on upper and lower eyelids. It is commonly seen in women with a peak incidence at 30–50 years. It is also considered as the cutaneous marker of underlying atherosclerosis along with the disturbed lipid metabolism. XP and corneal arcus are associated with increased levels of serum cholesterol and low-density lipoprotein (LDL cholesterol. Aims and Objectives: To study the clinical pattern of XP, its relationship with lipid profile and association with arcus cornea. Materials and Methods: This study was conducted at Department of Dermatology and Opthalmology, between August 2013 and January 2015. Patients with clinical diagnosis of XP who visited skin outpatient department and willing to undergo lipid profile test and eye examination were included in the study. Data regarding demographics, clinical findings, family history, and past history were noted along with the lipid profile details. Data of age-matched healthy controls were taken for comparison. The clinical profile of the participants was presented using frequency and proportions. Gender wise analysis comparing the lipid profile in cases with XP and without XP was done using independent sample t-test. Results: Total 49 patients of XP, 81.6% were females. Maximum, 35% patients were among 50–60 years of age and 69.4% were homemakers by occupation. The average lipid values were-cholesterol 210.57 mg%, triglyceride 123.06 mg%. LDL 142.79 mg% and VLDL 30.95 mg% among patients of XP. Arcus cornea was found in 20% cases of XP. Conclusions: Patients of XP requires proper investigation at the onset and regular follow-up thereafter for any altered lipid profile and early diagnosis of coronary artery disease.

  14. Xanthelasma Palpebrarum with Arcus Cornea: A Clinical and Biochemical Study.

    Science.gov (United States)

    Nair, Pragya Ashok; Patel, Chaitali R; Ganjiwale, Jaishree D; Diwan, Nilofar Gulamsha; Jivani, Nidhi Bhimjibhai

    2016-01-01

    Xanthelasma palpebrarum (XP) is characterized by sharply demarcated yellowish flat plaques on upper and lower eyelids. It is commonly seen in women with a peak incidence at 30-50 years. It is also considered as the cutaneous marker of underlying atherosclerosis along with the disturbed lipid metabolism. XP and corneal arcus are associated with increased levels of serum cholesterol and low-density lipoprotein (LDL) cholesterol. To study the clinical pattern of XP, its relationship with lipid profile and association with arcus cornea. This study was conducted at Department of Dermatology and Opthalmology, between August 2013 and January 2015. Patients with clinical diagnosis of XP who visited skin outpatient department and willing to undergo lipid profile test and eye examination were included in the study. Data regarding demographics, clinical findings, family history, and past history were noted along with the lipid profile details. Data of age-matched healthy controls were taken for comparison. The clinical profile of the participants was presented using frequency and proportions. Gender wise analysis comparing the lipid profile in cases with XP and without XP was done using independent sample t-test. Total 49 patients of XP, 81.6% were females. Maximum, 35% patients were among 50-60 years of age and 69.4% were homemakers by occupation. The average lipid values were-cholesterol 210.57 mg%, triglyceride 123.06 mg%. LDL 142.79 mg% and VLDL 30.95 mg% among patients of XP. Arcus cornea was found in 20% cases of XP. Patients of XP requires proper investigation at the onset and regular follow-up thereafter for any altered lipid profile and early diagnosis of coronary artery disease.

  15. Comparison of the characteristics in hen and quail corneas as experimental models of refractive surgery.

    Science.gov (United States)

    Gonçalves, G C; Pérez-Merino, P; Martínez-García, M C; Barcía, A; Merayo-Loves, J

    2016-07-01

    To compare the histological, morphological and the biophysical measurements between hen and quail corneas, in order to determine which of them were better suited for use as an animal model for research into corneal refractive surgery. A study was performed using the biophysical measurements of the cornea (curvature, thickness, refraction, and axial length) of 20 animals (10 hens and 10 quails). The corneas were then prepared for histological analysis under microscopy light. The analysis showed that both groups have the same number of corneal layers as the human cornea and with an evident Bowman's layer. The thickness of the hen cornea and axial length of the eye, 225.3±18.4μm and 12.8±0.25mm, respectively, were larger than that of the quail (Phen central cornea, 3.65±0.08mm, was greater than that for the quail (Ppower of each cornea was similar. The proportion of total corneal thickness of the hen stroma, 82.6%, was more similar to that of the human than was the quail stroma, 72.5%. Within the hen stroma, the density of keratocytes, 8.57±1.49 per 5,000μm(2), was about half that in the quail stroma (Phen cornea, the stromal thickness and proportional similarity of the corneal layers with human cornea, the hen maybe better than the quail as an alternative species suitable for use in studies of corneal refractive surgery. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  16. Melatonin Entrains PER2::LUC Bioluminescence Circadian Rhythm in the Mouse Cornea

    Science.gov (United States)

    Baba, Kenkichi; Davidson, Alec J.; Tosini, Gianluca

    2015-01-01

    Purpose Previous studies have reported the presence of a circadian rhythm in PERIOD2::LUCIFERASE (PER2::LUC) bioluminescence in mouse photoreceptors, retina, RPE, and cornea. Melatonin (MLT) modulates many physiological functions in the eye and it is believed to be one of the key circadian signals within the eye. The aim of the present study was to investigate the regulation of the PER2::LUC circadian rhythm in mouse cornea and to determine the role played by MLT. Methods Corneas were obtained from PER2::LUC mice and cultured to measure bioluminescence rhythmicity in isolated tissue using a Lumicycle or CCD camera. To determine the time-dependent resetting of the corneal circadian clocks in response to MLT or IIK7 (a melatonin type 2 receptor, MT2, agonist) was added to the cultured corneas at different times of the day. We also defined the location of the MT2 receptor within different corneal layers using immunohistochemistry. Results A long-lasting bioluminescence rhythm was recorded from cultured PER2::LUC cornea and PER2::LUC signal was localized to the corneal epithelium and endothelium. MLT administration in the early night delayed the cornea rhythm, whereas administration of MLT at late night to early morning advanced the cornea rhythm. Treatment with IIK7 mimicked the MLT phase-shifting effect. Consistent with these results, MT2 immunoreactivity was localized to the corneal epithelium and endothelium. Conclusions Our work demonstrates that MLT entrains the PER2::LUC bioluminescence rhythm in the cornea. Our data indicate that the cornea may represent a model to study the molecular mechanisms by which MLT affects the circadian clock. PMID:26207312

  17. An unusual case of nephrotic syndrome

    Directory of Open Access Journals (Sweden)

    M Sahay

    2016-01-01

    Full Text Available Nephrotic syndrome can be rarely due to inherited disorders of enzymes. One such variety is lecithin cholesterol acyltransferase deficiency. It leads to accumulation of unesterified cholesterol in the eye and other organs. We report a case of nephrotic syndrome with cloudy cornea and hypocholesterolemia with foam cells and lipid deposits on renal biopsy. Awareness about this rare disease may help in the early institution of specific measures to prevent progression to end-stage renal disease.

  18. A role for smoothened during murine lens and cornea development.

    Directory of Open Access Journals (Sweden)

    Janet J Y Choi

    Full Text Available Various studies suggest that Hedgehog (Hh signalling plays roles in human and zebrafish ocular development. Recent studies (Kerr et al., Invest Ophthalmol Vis Sci. 2012; 53, 3316-30 showed that conditionally activating Hh signals promotes murine lens epithelial cell proliferation and disrupts fibre differentiation. In this study we examined the expression of the Hh pathway and the requirement for the Smoothened gene in murine lens development. Expression of Hh pathway components in developing lens was examined by RT-PCR, immunofluorescence and in situ hybridisation. The requirement of Smo in lens development was determined by conditional loss-of-function mutations, using LeCre and MLR10 Cre transgenic mice. The phenotype of mutant mice was examined by immunofluorescence for various markers of cell cycle, lens and cornea differentiation. Hh pathway components (Ptch1, Smo, Gli2, Gli3 were detected in lens epithelium from E12.5. Gli2 was particularly localised to mitotic nuclei and, at E13.5, Gli3 exhibited a shift from cytosol to nucleus, suggesting distinct roles for these transcription factors. Conditional deletion of Smo, from ∼E12.5 (MLR10 Cre did not affect ocular development, whereas deletion from ∼E9.5 (LeCre resulted in lens and corneal defects from E14.5. Mutant lenses were smaller and showed normal expression of p57Kip2, c-Maf, E-cadherin and Pax6, reduced expression of FoxE3 and Ptch1 and decreased nuclear Hes1. There was normal G1-S phase but decreased G2-M phase transition at E16.5 and epithelial cell death from E14.5-E16.5. Mutant corneas were thicker due to aberrant migration of Nrp2+ cells from the extraocular mesenchyme, resulting in delayed corneal endothelial but normal epithelial differentiation. These results indicate the Hh pathway is required during a discrete period (E9.5-E12.5 in lens development to regulate lens epithelial cell proliferation, survival and FoxE3 expression. Defective corneal development occurs

  19. The filtering, clear-cornea diathermal keratostomy: a minor Danish multicenter study

    DEFF Research Database (Denmark)

    Kessing, S.V.; Nissen, O.I.; Thygesen, J.

    2008-01-01

    PURPOSE: Is the new micropenetrating, clear-cornea procedure, intrastromal diathermal keratostomy (IDK), an alternative to the intricate "modern trabeculectomy"? METHODS: Prospective multicenter study. Four surgeons from 4 Danish eye departments attended an IDK course and subsequently decided whe...

  20. Accelerating repaired basement membrane after bevacizumab treatment on alkali-burned mouse cornea

    Directory of Open Access Journals (Sweden)

    Koon-Ja Lee

    2013-04-01

    Full Text Available To understand the corneal regeneration induced by bevacizumab,we investigated the structure changes of stroma andbasement membrane regeneration. A Stick soaked in 0.5 NNaOH onto the mouse cornea and 2.5 mg/ml of bevacizumabwas delivered into an alkali-burned cornea (2 μl by subconjunctivalinjections at 1 hour and 4 days after injury. At 7 daysafter injury, basement membrane regeneration was observedby transmission electron microscope. Uneven and thin epithelialbasement membrane, light density of hemidesmosomes,and edematous collagen fibril bundles are shown in thealkali-burned cornea. Injured epithelial basement membraneand hemidesmosomes and edematous collagen fibril bundlesresulting from alkali-burned mouse cornea was repaired bybevacizumab treatment. This study demonstrates that bevacizumabcan play an important role in wound healing in thecornea by accelerating the reestablishment of basementmembrane integrity that leads to barriers for scar formation.[BMB Reports 2013; 46(4: 195-200

  1. Damage Threshold of In Vivo Rabbit Cornea by 2 micron Laser Irradiation

    National Research Council Canada - National Science Library

    Chen, Bo; Oliver, Jeffery; Dutta, Soumak; Rylander, III, Grady H; Thomsen, Sharon L; Welch, Ashley J

    2007-01-01

    To support refinement of the Maximum Permissible Exposure (MPE) safety limits, a series of experiments were conducted in vivo on Dutch Belted rabbit corneas to determine corneal minimum visible lesion thresholds...

  2. Successful treatment of Fusarium keratitis with cornea transplantation and topical and systemic voriconazole.

    NARCIS (Netherlands)

    Klont, R.R.; Eggink, C.A.; Rijs, A.J.M.M.; Wesseling, P.; Verweij, P.E.

    2005-01-01

    A case of invasive Fusarium keratitis in a previously healthy male patient was treated successfully with cornea transplantation and systemic and topical voriconazole after treatment failure with topical amphotericin B and systemic itraconazole. Topical voriconazole was well tolerated, and, in

  3. Mutations in LOXHD1, a Recessive-Deafness Locus, Cause Dominant Late-Onset Fuchs Corneal Dystrophy

    Science.gov (United States)

    Riazuddin, S. Amer; Parker, David S.; McGlumphy, Elyse J.; Oh, Edwin C.; Iliff, Benjamin W.; Schmedt, Thore; Jurkunas, Ula; Schleif, Robert; Katsanis, Nicholas; Gottsch, John D.

    2012-01-01

    Fuchs corneal dystrophy (FCD) is a genetic disorder of the corneal endothelium and is the most common cause of corneal transplantation in the United States. Previously, we mapped a late-onset FCD locus, FCD2, on chromosome 18q. Here, we present next-generation sequencing of all coding exons in the FCD2 critical interval in a multigenerational pedigree in which FCD segregates as an autosomal-dominant trait. We identified a missense change in LOXHD1, a gene causing progressive hearing loss in humans, as the sole variant capable of explaining the phenotype in this pedigree. We observed LOXHD1 mRNA in cultured human corneal endothelial cells, whereas antibody staining of both human and mouse corneas showed staining in the corneal epithelium and endothelium. Corneal sections of the original proband were stained for LOXHD1 and demonstrated a distinct increase in antibody punctate staining in the endothelium and Descemet membrane; punctate staining was absent from both normal corneas and FCD corneas negative for causal LOXHD1 mutations. Subsequent interrogation of a cohort of >200 sporadic affected individuals identified another 15 heterozygous missense mutations that were absent from >800 control chromosomes. Furthermore, in silico analyses predicted that these mutations reside on the surface of the protein and are likely to affect the protein's interface and protein-protein interactions. Finally, expression of the familial LOXHD1 mutant allele as well as two sporadic mutations in cells revealed prominent cytoplasmic aggregates reminiscent of the corneal phenotype. All together, our data implicate rare alleles in LOXHD1 in the pathogenesis of FCD and highlight how different mutations in the same locus can potentially produce diverse phenotypes. PMID:22341973

  4. Inflammation Modulatory Protein TSG-6 for Chemical Injuries to the Cornea

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-14-1-0495 TITLE: Inflammation Modulatory Protein TSG-6 for Chemical Injuries to the Cornea PRINCIPAL INVESTIGATOR...2017 4. TITLE AND SUBTITLE Inflammation Modulatory Protein TSG-6 for Chemical Injuries to the Cornea Infla I Inflammation Modulatory Protein TSG-6...anti-inflammatory protein , TSG-6, which has a novel mechanism of action. Chemical injuries of the eye are difficult to treat, and may lead to

  5. Morphology of endothelial cells from different regions of the equine cornea

    OpenAIRE

    Faganello, Cláudia Skilhan; Silva, Vanessa Ruiz Moura da; Andrade, Maria Cristina Caldart de; Carissimi, André Silva; Pigatto, João Antonio Tadeu

    2016-01-01

    ABSTRACT: The objective of this study was to evaluate the morphology of different regions of the equine cornea using optical microscopy. Both healthy eyes of eight horses, male or female, of different ages were evaluated. Corneas were stained with alizarin red vital dye and subsequently examined and photographed using optical microscopy. Corneal endothelial morphology of central, superior, inferior, temporal and nasal areas was assessed. One hundred endothelial cells from each corneal area we...

  6. [The value of methods for morphofunctional analysis of cornea in cataract surgery].

    Science.gov (United States)

    Borodina, N B; Kobzova, M V; Musaeva, G M

    2011-01-01

    The characteristics of morphofunctional status of cornea after extracapsular cataract extraction and phakoemulsification with IOL implantation (30 and 58 operations respectively) were analyzed in detail using up-to-date diagnostic techniques. The results of examination using developed algorithm including study of light transmission, refraction and protective function of cornea show advantage of microinvasive ultrasound technique of cataract surgery in terms of minimal impact on corneal structure, optical and biomechanical characteristics.

  7. Taurine effect on cytogenetic lesions in the cornea of mice exposed to 9 Gev proton irradiation

    International Nuclear Information System (INIS)

    Vorozhtsova, S.V.; Yartsev, E.I.

    1989-01-01

    Possibilities of preventive measures and treatment of cytogenetic injuries in the mice cornea, subjected to proton irradiation at 9 Gev were studied. Taurine containing solution (TCS) was used as a radiomodifying agent. It is shown that TCS application enables to decrease aberrant mitoses level in cornea epithelium cells of mice. Antiactinic effect of the above agent is determined by its considerable action on mitotic delay

  8. Tear dysfunction and the cornea: LXVIII Edward Jackson Memorial Lecture.

    Science.gov (United States)

    Pflugfelder, Stephen C

    2011-12-01

    To describe the cause and consequence of tear dysfunction-related corneal disease. Perspective on effects of tear dysfunction on the cornea. Evidence is presented on the effects of tear dysfunction on corneal morphology, function, and health, as well as efficacy of therapies for tear dysfunction-related corneal disease. Tear dysfunction is a prevalent eye disease and the most frequent cause for superficial corneal epithelial disease that results in corneal barrier disruption, an irregular optical surface, light scattering, optical aberrations, and exposure and sensitization of pain-sensing nerve endings (nociceptors). Tear dysfunction-related corneal disease causes irritation and visual symptoms such as photophobia and blurred and fluctuating vision that may decrease quality of life. Dysfunction of 1 or more components of the lacrimal functional unit results in changes in tear composition, including elevated osmolarity and increased concentrations of matrix metalloproteinases, inflammatory cytokines, and chemokines. These tear compositional changes promote disruption of tight junctions, alter differentiation, and accelerate death of corneal epithelial cells. Corneal epithelial disease resulting from tear dysfunction causes eye irritation and decreases visual function. Clinical and basic research has improved understanding of the pathogenesis of tear dysfunction-related corneal epithelial disease, as well as treatment outcomes. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Biomechanical behaviour - Anisotropy of eye cornea through experimental strip tests

    Science.gov (United States)

    Arsalan Khan, Mohammad; Elsheikh, Ahmed; Khan, Iqtedar Ahmad

    2018-02-01

    With the advent of research it was identified that material properties are responsible for errors in tonometry pressure (referred to as Goldmann IOP or IOPG) with the stiffening of a composite structure of corneal tissue in particular. Strip tensile tests are conducted to determine their stress-strain relationship for the purpose to study the behaviour of material properties of cornea. Specimens are taken from the superior-inferior (vertical) and temporal- nasal (horizontal) directions. Testing is performed on an Instron machine, under different rate of loading conditions. First set of experiment, with single strain rate, is executed on eyes having random population. While the second set of experiment is executed on eyes of the same animal in both directions, and different strain rates are applied each specimen. Relatively, the first set of experiment is found to be slightly different and less accurate. In general, it is found that the vertical specimen is 34% on an average stiffer than the horizontal specimen compared to Kampmeier et al. of 20% (studied in 2000) and Defu Wang of 15% (studied in 2007). Curve fitting coefficients are also evaluated for 4-degree polynomial. The anisotropy is evident by plotting the ratio of E-tangent value of vertical Ev and horizontal Eh against stresses with individual strain rates. The value of Ev/Eh increases with slightly slow rate with stresses as compared to achieved through slow strain rates.

  10. Cross-linking da cornea: protocolo padrão

    Directory of Open Access Journals (Sweden)

    Marcony R. Santhiago

    Full Text Available RESUMO O objetivo desta revisão é de determinar as indicações e eficácia da cirurgia que promove novas ligações covalentes entre as fibras de colágeno da córnea, conhecida como Cross-Linking (CXL, assim como esclarecer seus objetivos. O ceratocone é uma doença ectasica da córnea, bilateral, assimétrica, que, principalmente, cursa com encurvamento e afinamentos progressivo, e se inicia em geral na segunda década de vida. O uso primário do CXL tem sido na interrupção da progressão do Ceratocone. Apesar do conhecido encurvamento no estroma da córnea ocorrer nesses pacientes, a fisiopatologia por trás do ceratocone ainda é desconhecida e parece ser multifatorial. Pela evidencia literária disponível até o momento, o CXL da córnea esta, portanto indicado nos pacientes com doença em progressão. Concluímos que existe evidencia suficiente para afirmar que o CXL da córnea é eficaz na estabilização da doença ectásica da cornea.

  11. Polymicrobial Infection of the Cornea Due to Contact Lens Wear

    Directory of Open Access Journals (Sweden)

    Selçuk Sızmaz

    2016-04-01

    Full Text Available A 38-year-old male presented with pain and redness in his left eye. He had a history of wearing contact lenses. His ophthalmic examination revealed a large corneal ulcer with surrounding infiltrate. Cultures were isolated from the contact lenses, lens solutions, storage cases, and conjunctivae of both eyes and also corneal scrapings of the left eye. Fortified vancomycin and amikacin drops were started hourly. Culture results of conjunctivae of each eye and left cornea were positive for Pseudomonas aeruginosa; cultures from the contact lenses, lens solution and storage case of both eyes revealed Pseudomonas aeruginosa and Alcaligenes xylosoxidans. Polymerase chain reaction of the corneal scraping was positive for Acanthameoba. The topical antibiotics were changed with ones that both bacteria were sensitive to and anti-amoebic therapy was added. The patient had two recurrences following initial presentation despite intensive therapy. Keratitis occurred due to multiple pathogens; the relapsing course despite adequate therapy is potentially associated with this polymicrobial etiology.

  12. Wound-Healing Studies in Cornea and Skin: Parallels, Differences and Opportunities.

    Science.gov (United States)

    Bukowiecki, Anne; Hos, Deniz; Cursiefen, Claus; Eming, Sabine A

    2017-06-12

    The cornea and the skin are both organs that provide the outer barrier of the body. Both tissues have developed intrinsic mechanisms that protect the organism from a wide range of external threats, but at the same time also enable rapid restoration of tissue integrity and organ-specific function. The easy accessibility makes the skin an attractive model system to study tissue damage and repair. Findings from skin research have contributed to unravelling novel fundamental principles in regenerative biology and the repair of other epithelial-mesenchymal tissues, such as the cornea. Following barrier disruption, the influx of inflammatory cells, myofibroblast differentiation, extracellular matrix synthesis and scar formation present parallel repair mechanisms in cornea and skin wound healing. Yet, capillary sprouting, while pivotal in proper skin wound healing, is a process that is rather associated with pathological repair of the cornea. Understanding the parallels and differences of the cellular and molecular networks that coordinate the wound healing response in skin and cornea are likely of mutual importance for both organs with regard to the development of regenerative therapies and understanding of the disease pathologies that affect epithelial-mesenchymal interactions. Here, we review the principal events in corneal wound healing and the mechanisms to restore corneal transparency and barrier function. We also refer to skin repair mechanisms and their potential implications for regenerative processes in the cornea.

  13. Dendritic cells in the cornea during Herpes simplex viral infection and inflammation.

    Science.gov (United States)

    Kwon, Min S; Carnt, Nicole A; Truong, Naomi R; Pattamatta, Ushasree; White, Andrew J; Samarawickrama, Chameen; Cunningham, Anthony L

    2017-11-10

    Herpes simplex keratitis is commonly caused by Herpes simplex virus type 1, which primarily infects eyelids, corneas, or conjunctiva. Herpes simplex virus type 1-through sophisticated interactions with dendritic cells (DCs), a type of antigen-presenting cell)-initiates proinflammatory responses in the cornea. Corneas were once thought to be an immune-privileged region; however, with the recent discovery of DCs that reside in the cornea, this long-held conjecture has been overturned. Therefore, evaluating the clinical, preclinical, and cell-based studies that investigate the roles of DCs in corneas infected with Herpes simplex virus is critical. With in vivo confocal microscopy, animal models, and cell culture experiments, we may further the understanding of the sophisticated interactions of Herpes simplex virus with DCs in the cornea and the molecular mechanism associated with it. It has been shown that specific differentiation of DCs using immunohistochemistry, flow cytometry, and polymerase chain reaction analysis in both human and mice tissues and viral tissue infections are integral to increasing understanding. As for in vivo confocal microscopy, it holds promise as it is the least invasive and a real-time investigation. These tools will facilitate the discovery of various targets to develop new treatments. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Intrastromal Injection of China Painting Ink in Corneas of Male Rabbits: Clinical and Histological Study.

    Science.gov (United States)

    Alsmman Hassan, Alahmady Hamad; Abd Elhaliem Soliman, Nesreen Gamal-Eldeen

    2016-01-01

    Background. Many patients with corneal opacity or complicated cataract in blind eye ask for cosmoses. In this study we tried to investigate the staining of corneas of male rabbits by Rotring China painting ink and to study the histological changes. Method. 10 eyes of 10 male Baladi Egyptian rabbits were injected (0.1 mL) intrastromally in the cornea by the use of China painting ink (Rotring Tinta China) through insulin syringe (27-gauge needle) by single injection; clinical follow-up is for 6 months and lastly the rabbits were scarified and the stained eyes were enucleated for histological analysis. Results. Clinically the stain was stable in color and distribution in corneas with no major complications. Histological results of the stained rabbit corneas showed blackish pigmentation in the corneal stroma without any inflammatory cellular infiltration. Some fibroblast cells had pigment granules in their cytoplasm in the adjacent layers. Conclusion. Corneal staining by China painting ink is effective and safe in staining of male rabbits cornea; however further study in human corneas with longer follow-up period is advisable.

  15. The structural response of the cornea to changes in stromal hydration.

    Science.gov (United States)

    Hayes, Sally; White, Tomas; Boote, Craig; Kamma-Lorger, Christina S; Bell, James; Sorenson, Thomas; Terrill, Nick; Shebanova, Olga; Meek, Keith M

    2017-06-01

    The primary aim of this study was to quantify the relationship between corneal structure and hydration in humans and pigs. X-ray scattering data were collected from human and porcine corneas equilibrated with polyethylene glycol (PEG) to varying levels of hydration, to obtain measurements of collagen fibril diameter, interfibrillar spacing (IFS) and intermolecular spacing. Both species showed a strong positive linear correlation between hydration and IFS 2 and a nonlinear, bi-phasic relationship between hydration and fibril diameter, whereby fibril diameter increased up to approximately physiological hydration, H = 3.0, with little change thereafter. Above H = 3.0, porcine corneas exhibited a larger fibril diameter than human corneas ( p < 0.001). Intermolecular spacing also varied with hydration in a bi-phasic manner but reached a maximum value at a lower hydration ( H = 1.5) than fibril diameter. Human corneas displayed a higher intermolecular spacing than porcine corneas at all hydrations ( p < 0.0001). Human and porcine corneas required a similar PEG concentration to reach physiological hydration, suggesting that the total fixed charge that gives rise to the swelling pressure is the same. The difference in their structural responses to hydration can be explained by variations in molecular cross-linking and intra/interfibrillar water partitioning. © 2017 The Authors.

  16. Intrastromal Injection of China Painting Ink in Corneas of Male Rabbits: Clinical and Histological Study

    Directory of Open Access Journals (Sweden)

    Alahmady Hamad Alsmman Hassan

    2016-01-01

    Full Text Available Background. Many patients with corneal opacity or complicated cataract in blind eye ask for cosmoses. In this study we tried to investigate the staining of corneas of male rabbits by Rotring China painting ink and to study the histological changes. Method. 10 eyes of 10 male Baladi Egyptian rabbits were injected (0.1 mL intrastromally in the cornea by the use of China painting ink (Rotring Tinta China through insulin syringe (27-gauge needle by single injection; clinical follow-up is for 6 months and lastly the rabbits were scarified and the stained eyes were enucleated for histological analysis. Results. Clinically the stain was stable in color and distribution in corneas with no major complications. Histological results of the stained rabbit corneas showed blackish pigmentation in the corneal stroma without any inflammatory cellular infiltration. Some fibroblast cells had pigment granules in their cytoplasm in the adjacent layers. Conclusion. Corneal staining by China painting ink is effective and safe in staining of male rabbits cornea; however further study in human corneas with longer follow-up period is advisable.

  17. The Ties that Bind (the Igh Locus).

    Science.gov (United States)

    Krangel, Michael S

    2016-05-01

    Immunoglobulin heavy-chain locus V(D)J recombination requires a 3D chromatin organization which permits widely distributed variable (V) gene segments to contact distant diversity (D) and joining (J) gene segments. A recent study has identified key nodes in the locus interactome, paving the way for new molecular insights into how the locus is configured for recombination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Mapping X-linked ophthalmic diseases. IV. Provisional assignment of the locus for X-linked congenital cataracts and microcornea (the Nance-Horan syndrome) to Xp22.2-p22.3.

    Science.gov (United States)

    Lewis, R A; Nussbaum, R L; Stambolian, D

    1990-01-01

    The Nance-Horan syndrome (NHS) is an infrequent X-linked disorder typified by dense congenital central cataracts, microcornea, anteverted and simplex pinnae, brachymetacarpalia, and numerous dental anomalies. The regional location of the genetic mutation causing NHS is unknown. The authors applied the modern molecular techniques of analysis of restriction fragment length polymorphisms to five multigenerational kindreds in which NHS segregated. Provisional linkage is established to two DNA markers--DXS143 at Xp22.3-p22.2 and DXS43 at Xp22.2. Regional localization of NHS will provide potential antenatal diagnosis in families at risk for the disease and will enhance understanding of the multifaceted genetic defects.

  19. Rothmund-thomson Syndrome

    Directory of Open Access Journals (Sweden)

    M Z Mani

    1979-01-01

    Full Text Available A case of Rothmund-Thomson syndrome in an 8-year-old Indian male is reported. The patient had bilaterally symmertrical superficial pigmentary deposition of thin nebulae in the lower one-third of the cornea and oonjunctiva. Urinary togmphy rcvmw a dibasic aininoacid with excretion of arginine, lysine;.hmncicystine and glycine. Other features of interest in this patient were onset at the age of 8 days and start of the disease on the hands and feet rather than face. The patient also developed repeated ulcerations on the hands and feet subsequent to minor trauma.

  20. Use of glycerol-preserved corneas for corneal transplants

    Directory of Open Access Journals (Sweden)

    Neeti Gupta

    2017-01-01

    Full Text Available Purpose: This study was carried out to see the results of glycerol-preserved cornea (GPC in emergency situation when fresh corneal tissue was not available. The aim was to study the outcome of corneal transplantation using GPC. Methods: This was a retrospective study. The medical records of all the patients were reviewed, who underwent keratoplasty using “GPC” during the period from October 2011 to December 2015. The indication of keratoplasty, duration of preservation of the GPC, and its outcome were analyzed. Descriptive statistics were applied. Results: Out of the 222 penetrating keratoplasty (PKP performed over the study period, the GPC was used in 34 patients (males = 31, 91.2% aged 15–74 years. Therapeutic keratoplasty was performed in all cases in this cohort except one in which tectonic keratoplasty was done. The primary indication of PKP (91.2% was infectious keratitis. Of these, 20 (64.5% patients presented with perforated corneal ulcers. Post-PKP, ocular anatomy was preserved in 91.2%, and visual acuity of perception of light positive and accurate projection of rays in all the quadrants was obtained in 76.5% cases. Complications included glaucoma (n = 12, 35.1%, phthisis bulbi (n = 2, 5.9%, and graft reinfection and endophthalmitis after PKP (n = 1, 2.9%. The secondary procedure post-GPC and PKP were trabeculectomy with mitomycin C (n = 7, 58.3% in patients not controlled on topical antiglaucoma medication. Optical keratoplasty was performed in (n = 3 8.8% patients and triple procedure in (n = 2 5.8% patients with good visual acuity postprocedure. Conclusions: Acellular GPCs are useful in emergency keratoplasty to avoid loss of vision and can save the eye.

  1. Optical coherent tomography measurements of the diffusion rate of water and drugs in an isolated and whole cornea

    International Nuclear Information System (INIS)

    Larin, Kirill V; Ghosn, M G

    2006-01-01

    The passive diffusion of drugs through the epithelial surfaces of an eye (the most widespread method for medical treatment of various diseases) is considered. The permeability of water and drugs through rabbit cornea was measured in the isolated cornea (separate from an eye) and in the whole cornea. The permeability coefficients of water and dexamethasone were estimated by the method of optical coherence tomography (OCT). Because multiple photon scattering introduces noise and distortions to the OCT signal, measurements were performed at depths up to 500 μm where most likely single scattering of light occurs in cornea. It is shown that the permeability coefficients in the isolated and whole cornea strongly differ from each other. For example, the water permeability in the isolated and whole cornea is (7.09±0.12)x10 -5 and (1.71±0.51)x10 -5 cm s -1 , respectively. (special issue devoted to multiple radiation scattering in random media)

  2. Therapeutic effect of para aminobenzoic acid (PABA) on the rat cornea administered in different ways after x-irradiation

    International Nuclear Information System (INIS)

    Panova, I.G.; Mel'nikova, I.I.; Stroeva, O.G.

    1997-01-01

    Comparative analysis of cytological state of nuclear apparatus in the mice cornea basal layer is carried out by two various method of introducing the para-aminobenzoic acid (PABA) after x-ray irradiation: 1) subcutaneous injections and 2) application of the solution on the cornea. The fact that PABA produced medicinal effect on the cornea of the irradiated mice by subcutaneous injections, shows that this action proceeds on the whole-body level

  3. Locus: mede-ontwikkelaar van inclusieve arbeidsorganisaties

    NARCIS (Netherlands)

    Beukema, Leni; de Lange, Annet; Wielenga-Meijer, Etty; Duijker, Theo; Hanstede, Bram

    2018-01-01

    in deze bijdrage wordt Locus beschreven, een netwerk waarin publieke partijen en grote, landelijk opererende bedrijven samenwerken om mensen met een afstand tot de arbeidsmarkt duurzaam aan het werk te helpen. Het hoofdstuk start met de ontstaansgeschiedenis en benadering van Locus. Vervolgens wordt

  4. Clinical, biochemical, and neuropsychiatric evaluation of a patient with a contiguous gene syndrome due to a microdeletion Xp11.3 including the Norrie disease locus and monoamine oxidase (MAOA and MAOB) genes.

    Science.gov (United States)

    Collins, F A; Murphy, D L; Reiss, A L; Sims, K B; Lewis, J G; Freund, L; Karoum, F; Zhu, D; Maumenee, I H; Antonarakis, S E

    1992-01-01

    Norrie disease is a rare X-linked recessive disorder characterized by blindness from infancy. The gene for Norrie disease has been localized to Xp11.3. More recently, the genes for monoamine oxidase (MAOA, MAOB) have been mapped to the same region. This study evaluates the clinical, biochemical, and neuropsychiatric data in an affected male and 2 obligate heterozygote females from a single family with a submicroscopic deletion involving Norrie disease and MAO genes. The propositus was a profoundly retarded, blind male; he also had neurologic abnormalities including myoclonus and stereotopy-habit disorder. Both obligate carrier females had a normal IQ. The propositus' mother met diagnostic criteria for "chronic hypomania and schizotypal features." The propositus' MAO activity was undetectable and the female heterozygotes had reduced levels comparable to patients receiving MAO inhibiting antidepressants. MAO substrate and metabolite abnormalities were found in the propositus' plasma and CSF. This study indicates that subtle biochemical and possibly neuropsychiatric abnormalities may be detected in some heterozygotes with the microdeletion in Xp11.3 due to loss of the gene product for the MAO genes; this deletion can also explain some of the complex phenotype of this contiguous gene syndrome in the propositus.

  5. Cholesterol biosynthesis by the cornea. Comparison of rates of sterol synthesis with accumulation during early development

    International Nuclear Information System (INIS)

    Cenedella, R.J.; Fleschner, C.R.

    1989-01-01

    The origin of the cholesterol needed by the cornea for growth and cell turnover was addressed by comparing absolute rates of sterol synthesis with rates of sterol accumulation during early development of the rabbit. Linearity of incorporation of 3 H 2 O and [ 14 C]mevalonate into digitonin-precipitable sterols with time of incubation in vitro and a lack of accumulation of 14 C in intermediates of sterol biosynthesis indicated that tritiated water can validly be used to measure rates of sterol synthesis by the cornea. The rate of sterol synthesis per unit weight of rabbit cornea was constant between 14 and 60 days of age at an average 1.03 nmol of 3 H of 3 H 2 O incorporated/mg dry cornea per 8 h. Essentially all of the synthesized cholesterol and most of the cholesterol mass was present in corneal epithelium. The cumulative sterol synthesized over the 46-day period studied exceeded the observed rate of cholesterol accumulation by sixfold. Cholesterol synthesized in excess of the growth requirement was likely used to support turnover of the epithelium which was estimated at 9 days. Removal of cholesterol from the cornea by excretion into tear fluid and clearance by high density lipoproteins are also considered

  6. Pharmacokinetics of chlorhexidine gluconate 0.02% in the rabbit cornea.

    Science.gov (United States)

    Xuguang, Sun; Yanchuang, Liang; Feng, Zhang; Shiyun, Luo; Xiaotang, Yin

    2006-08-01

    The aim of this study was to determine the pharmacokinetic parameters of chlorhexidine gluconate (CHG) in the rabbit cornea. Each eye of 16 New Zealand white rabbits were topically instilled with 50 microL of CHG 0.02% eye drops twice with a 5-min interval. Four (4) corneas of 2 rabbits were harvested at each time point. The concentration of CHG in the cornea was determined with high-performance liquid chromatography (HPLC) and 387 software to simulate the pharmacokinetic parameters. The concentration of CHG in the cornea displayed an open two-compartment model. Tmax was 13.75 min, Cmax 0.713 microg.g1, clearance rate 1.64 microg.g-1.min-1, and t1/2alpha, t1/2beta, and t1/2ka was 2.65, 48.72, and 2.67 min, respectively. The concentration of CHG in the rabbit cornea could be determined by means of HPLC. The maximum concentration of CHG in the corneal tissue was much higher than the trophozoite minimum amoebicidal concentration (TMAC) in vitro.

  7. Cornea nerve fiber quantification and construction of phenotypes in patients with fibromyalgia.

    Science.gov (United States)

    Oudejans, Linda; He, Xuan; Niesters, Marieke; Dahan, Albert; Brines, Michael; van Velzen, Monique

    2016-03-23

    Cornea confocal microscopy (CCM) is a novel non-invasive method to detect small nerve fiber pathology. CCM generally correlates with outcomes of skin biopsies in patients with small fiber pathology. The aim of this study was to quantify the morphology of small nerve fibers of the cornea of patients with fibromyalgia in terms of density, length and branching and further phenotype these patients using standardized quantitative sensory testing (QST). Small fiber pathology was detected in the cornea of 51% of patients: nerve fiber length was significantly decreased in 44% of patients compared to age- and sex-matched reference values; nerve fiber density and branching were significantly decreased in 10% and 28% of patients. The combination of the CCM parameters and sensory tests for central sensitization, (cold pain threshold, mechanical pain threshold, mechanical pain sensitivity, allodynia and/or windup), yielded four phenotypes of fibromyalgia patients in a subgroup analysis: one group with normal cornea morphology without and with signs of central sensitization, and a group with abnormal cornea morphology parameters without and with signs of central sensitization. In conclusion, half of the tested fibromyalgia population demonstrates signs of small fiber pathology as measured by CCM. The four distinct phenotypes suggest possible differences in disease mechanisms and may require different treatment approaches.

  8. Raman Microscopy: A Noninvasive Method to Visualize the Localizations of Biomolecules in the Cornea.

    Science.gov (United States)

    Kaji, Yuichi; Akiyama, Toshihiro; Segawa, Hiroki; Oshika, Tetsuro; Kano, Hideaki

    2017-11-01

    In vivo and in situ visualization of biomolecules without pretreatment will be important for diagnosis and treatment of ocular disorders in the future. Recently, multiphoton microscopy, based on the nonlinear interactions between molecules and photons, has been applied to reveal the localizations of various molecules in tissues. We aimed to use multimodal multiphoton microscopy to visualize the localizations of specific biomolecules in rat corneas. Multiphoton images of the corneas were obtained from nonlinear signals of coherent anti-Stokes Raman scattering, third-order sum frequency generation, and second-harmonic generation. The localizations of the adhesion complex-containing basement membrane and Bowman layer were clearly visible in the third-order sum frequency generation images. The fine structure of type I collagen was observed in the corneal stroma in the second-harmonic generation images. The localizations of lipids, proteins, and nucleic acids (DNA/RNA) was obtained in the coherent anti-Stokes Raman scattering images. Imaging technologies have progressed significantly and been applied in medical fields. Optical coherence tomography and confocal microscopy are widely used but do not provide information on the molecular structure of the cornea. By contrast, multiphoton microscopy provides information on the molecular structure of living tissues. Using this technique, we successfully visualized the localizations of various biomolecules including lipids, proteins, and nucleic acids in the cornea. We speculate that multiphoton microscopy will provide essential information on the physiological and pathological conditions of the cornea, as well as molecular localizations in tissues without pretreatment.

  9. Sorption of sodium hydroxide by type I collagen and bovine corneas.

    Science.gov (United States)

    Whikehart, D R; Edwards, W C; Pfister, R R

    1991-01-01

    There are no quantitative studies on the uptake of alkali into corneal tissues. To study this phenomenon, both type I collagen and bovine corneas were incubated in sodium hydroxide (NaOH) under varying conditions for periods up to 27.5 h. The sorption (absorption or adsorption) of the alkali to protein and tissue was measured as the quantity of NaOH no longer available for titration to neutrality with hydrochloric acid. Sorption was found to be dependent on the concentration of NaOH (0.01-1 N) but independent of the incubation temperature (4-35 degrees C). In whole cornea, sorption of 1 N NaOH began immediately and increased with time up to 6 h. After 6 h, sorption decreased, together with the observed degradation and solubilization of the tissue. Stripping of the corneal endothelium alone or of the endothelium and epithelium increased sorption in a similar manner when compared to whole corneas for periods up to 4 h. These observations are compatible with ionic and nonionic bonding of hydroxide ions to collagen (including that of the cornea) and the subsequent release of hydroxide ions during hydrolysis of the protein itself. Indirect evidence also suggests the inclusion of quantities of unbound hydroxide ions in hydrated gels of glycosaminoglycans. It is proposed that in a chemical burn of the cornea, alkali is both stored in the tissue (by sorption) and reacted with it (by hydrolysis), without any net consumption of alkali taking place.

  10. Accelerating repaired basement membrane after bevacizumab treatment on alkali-burned mouse cornea

    Science.gov (United States)

    Lee, Koon-Ja; Lee, Ji-Young; Lee, Sung Ho; Choi, Tae Hoon

    2013-01-01

    To understand the corneal regeneration induced by bevacizumab, we investigated the structure changes of stroma and basement membrane regeneration. A Stick soaked in 0.5 N NaOH onto the mouse cornea and 2.5 mg/ml of bevacizumab was delivered into an alkali-burned cornea (2 μl) by subconjunctival injections at 1 hour and 4 days after injury. At 7 days after injury, basement membrane regeneration was observed by transmission electron microscope. Uneven and thin epithelial basement membrane, light density of hemidesmosomes, and edematous collagen fibril bundles are shown in the alkali-burned cornea. Injured epithelial basement membrane and hemidesmosomes and edematous collagen fibril bundles resulting from alkali-burned mouse cornea was repaired by bevacizumab treatment. This study demonstrates that bevacizumab can play an important role in wound healing in the cornea by accelerating the reestablishment of basement membrane integrity that leads to barriers for scar formation. [BMB Reports 2013; 46(4): 195-200] PMID:23615260

  11. Factors affecting the serological testing of cadaveric donor cornea

    Directory of Open Access Journals (Sweden)

    Anuradha Raj

    2018-01-01

    will be done in < 10 hours(h after death which can improve the safety and utility of the donor cornea.

  12. Factors affecting the serological testing of cadaveric donor cornea.

    Science.gov (United States)

    Raj, Anuradha; Mittal, Garima; Bahadur, Harsh

    2018-01-01

    The purpose of this study was to evaluate the serological profile of the eye donors and to study the influence of various factors on serological test results. A cross-sectional, observational study was conducted, and data of 509 donors were reviewed from the records of eye bank from December 2012 to June 2017. Various details of donors analyzed included the age, sex of the donor, cause of death, source of tissue, time since blood collection after death, macroscopic appearance of blood sample, and details of discarded tissues. Serological examination of blood was performed for human immunodeficiency virus (HIV), hepatitis B virus, hepatitis C virus (HCV), venereal disease research laboratory (VDRL), and serology reports reactive or nonreactive were analyzed. Among the 509 donors, 295 (58%) were male, and 420 (82.50%) belonged to age group ≥60 years. Most donors (354, 69.5%) died due to cardiac arrest. Macroscopically, sera were normal in the majority of 488 (95.9%) cases. Among 509 donors, 475 (93.3%) were nonreactive, 12 (2.4%) donors were found to be reactive to hepatitis B surface antigen (HBsAg), and 1 (0.2%) was reactive to HCV, but no donor serology was reactive to HIV or VDRL. Twenty-one (4.12%) donors' sera were not fit for serological testing. Among all donors, 475 (93.32%) donors were accepted and 34 (6.67%) were rejected or discarded on the basis of serological testing. Cause of death and macroscopic aspect of sera influenced the serological results in a highly significant manner (P = 0.00). Acceptance or rejection of the donor was significantly influenced by the serological results of the donor (P = 0.00). The seroprevalence among eye donor for HBsAg and HCV was 12 (2.4%) and 1 (0.2%), respectively. Factors such as cause of death and macroscopic aspect of sera influence the serological results. Time since blood collection or sampling will not show any impact on viral serological results if postmortem sampling will be done in donor cornea.

  13. Systematic assessment of microneedle injection into the mouse cornea.

    Science.gov (United States)

    Matthaei, Mario; Meng, Huan; Bhutto, Imran; Xu, Qingguo; Boelke, Edwin; Hanes, Justin; Jun, Albert S

    2012-06-20

    Corneal intrastromal injection is an important mode of gene-vector application to subepithelial layers. In a mouse model, this procedure is substantially complicated by the reduced corneal dimensions. Furthermore, it may be difficult to estimate the corneal area reached by the volume of a single injection. This study aimed to investigate intrastromal injections into the mouse cornea using different microneedles and to quantify the effect of injecting varying volumes. A reproducible injection technique is described. Forty eyes of 20 129 Sv/J mice were tested. India ink was intrastromally injected using 30° beveled 33 G needles, tri-surface 25° beveled 35 G needles, or hand-pulled and 25° beveled glass needles. Each eye received a single injection of a volume of 1 or 2 μL. Corneoscleral buttons were fixed and flat mounted for computer-assisted quantification of the affected corneal area. Histological assessment was performed to investigate the intrastromal location of the injected dye. A mean corneal area of 5.0 ± 1.4 mm(2) (mean ± SD) and 7.7 ± 1.4 mm(2) was covered by intrastromal injections of 1 and 2 μL, respectively. The mean percentage of total corneal area reached ranged from 39% to 53% for 1 μL injections, and from 65% to 81% for 2 μL injections. Injections using the 33 G needles tended to provide the highest distribution area. Perforation rates were 8% for 30° beveled 33 G needles and 44% for tri-surface beveled 35 G needles. No perforation was observed with glass needle; however, intrastromal breakage of needle tips was noted in 25% of these cases. Intracorneal injection using a 30° beveled 33 G needle was safe and effective. The use of tri-surface beveled 35 G needles substantially increased the number of corneal perforations. Glass needles may break inside the corneal stroma. Injections of 1 μL and 2 μL resulted in an overall mean of 49% and 73% respectively of total corneal area involved.

  14. Systematic assessment of microneedle injection into the mouse cornea

    Directory of Open Access Journals (Sweden)

    Matthaei Mario

    2012-06-01

    Full Text Available Abstract Background Corneal intrastromal injection is an important mode of gene-vector application to subepithelial layers. In a mouse model, this procedure is substantially complicated by the reduced corneal dimensions. Furthermore, it may be difficult to estimate the corneal area reached by the volume of a single injection. This study aimed to investigate intrastromal injections into the mouse cornea using different microneedles and to quantify the effect of injecting varying volumes. A reproducible injection technique is described. Methods Forty eyes of 20 129 Sv/J mice were tested. India ink was intrastromally injected using 30° beveled 33 G needles, tri-surface 25° beveled 35 G needles, or hand-pulled and 25° beveled glass needles. Each eye received a single injection of a volume of 1 or 2 μL. Corneoscleral buttons were fixed and flat mounted for computer-assisted quantification of the affected corneal area. Histological assessment was performed to investigate the intrastromal location of the injected dye. Results A mean corneal area of 5.0 ±1.4 mm2 (mean ± SD and 7.7 ±1.4 mm2 was covered by intrastromal injections of 1 and 2 μL, respectively. The mean percentage of total corneal area reached ranged from 39% to 53% for 1 μL injections, and from 65% to 81% for 2 μL injections. Injections using the 33 G needles tended to provide the highest distribution area. Perforation rates were 8% for 30° beveled 33 G needles and 44% for tri-surface beveled 35 G needles. No perforation was observed with glass needle; however, intrastromal breakage of needle tips was noted in 25% of these cases. Conclusions Intracorneal injection using a 30° beveled 33 G needle was safe and effective. The use of tri-surface beveled 35 G needles substantially increased the number of corneal perforations. Glass needles may break inside the corneal stroma. Injections of 1 μL and 2 μL resulted in an overall mean of 49% and 73% respectively

  15. EL LOCUS DE DISTRIBUCION COMO COROLARIO DEL LOCUS DE CONTROL

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    Luisa Mayoral

    2009-01-01

    Full Text Available Este es un artículo científico acerca del Locus de Distribución, surgido de un estudio realizado con una población de docentes y alumnos universitarios. Respecto de los primeros, se ha indagado acerca de las atribuciones que se realizaban en torno a las recompensas y sanciones, que ellos distribuían a sus alumnos. Respecto de los segundos, se ha buscado determinar la valoración que estos realizaban de sus profesores, en términos de aquellas atribuciones. Para ello, se utilizaron dos paradigmas clásicamente empleados para verificar la existencia de una norma: el paradigma de la autopresentación (docentes, y el paradigma de los juicios (alumnos. La cuestión planteada fue determinar si en el caso de los comportamientos distributivos de refuerzos, las causas se atribuían a variables externas -en particular a los receptores de esos refuerzos- y si esas formas de atribución eran conocidas y valoradas o no, por los alumnos. De los resultados, surgió la confirmación de nuestra hipótesis de explicaciones externas en materia de comportamientos distributivos de sanciones en el ámbito de la docencia y la valoración positiva de estas atribuciones por los alumnos.

  16. Second Harmonic Generation Imaging Analysis of Collagen Arrangement in Human Cornea.

    Science.gov (United States)

    Park, Choul Yong; Lee, Jimmy K; Chuck, Roy S

    2015-08-01

    To describe the horizontal arrangement of human corneal collagen bundles by using second harmonic generation (SHG) imaging. Human corneas were imaged with an inverted two photon excitation fluorescence microscope. The excitation laser (Ti:Sapphire) was tuned to 850 nm. Backscatter signals of SHG were collected through a 425/30-nm bandpass emission filter. Multiple, consecutive, and overlapping image stacks (z-stacks) were acquired to generate three dimensional data sets. ImageJ software was used to analyze the arrangement pattern (irregularity) of collagen bundles at each image plane. Collagen bundles in the corneal lamellae demonstrated a complex layout merging and splitting within a single lamellar plane. The patterns were significantly different in the superficial and limbal cornea when compared with deep and central regions. Collagen bundles were smaller in the superficial layer and larger in deep lamellae. By using SHG imaging, the horizontal arrangement of corneal collagen bundles was elucidated at different depths and focal regions of the human cornea.

  17. Air-pulse OCE for assessment of age-related changes in mouse cornea in vivo

    International Nuclear Information System (INIS)

    Li, Jiasong; Wang, Shang; Singh, M; Larin, K V; Aglyamov, S; Emelianov, S; Twa, M D

    2014-01-01

    We demonstrate the use of phase-stabilized swept source optical coherence elastography (PhS-SSOCE) to assess the relaxation rate of deformation created by a focused air-pulse in tissue-mimicking gelatin phantoms of various concentrations and mouse corneas of different ages in vivo. The results show that the relaxation rate can be quantified and is different for gels with varying concentrations of gelatin and mouse corneas of different ages. The results indicate that gel phantoms with higher concentrations of gelatin as well as older mouse corneas have faster relaxation rates indicating stiffer material. This non-contact and non-invasive measurement technique utilizes low surface displacement amplitude (in µm scale) for tissue excitation and, therefore, can be potentially used to study the biomechanical properties of ocular and other sensitive tissues. (letter)

  18. Anterior segment optical coherence tomography for evaluation of cornea and ocular surface

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    Mittanamalli S Sridhar

    2018-01-01

    Full Text Available Current corneal assessment technologies make the process of corneal evaluation extremely fast and simple. Several devices and technologies allow to explore and manage patients better. Optical coherence tomography (OCT technology has evolved over the years, and hence a detailed evaluation of anterior segment (AS structures such as cornea, conjunctiva, tear meniscus, anterior chamber, iris, and crystalline lens has been possible in a noncontact and safe procedure. The purpose of this special issue is to present and update in the evaluation of cornea and ocular surface, and this paper reviews a description of the AS-OCT, presenting the technology and common clinical uses of OCT in the management of diseases involving cornea and ocular surface to provide an updated information of the clinical recommendations of this technique in eye care practice.

  19. Intra-Ocular Pressure Measurement in a Patient with a Thin, Thick or Abnormal Cornea.

    Science.gov (United States)

    Clement, Colin I; Parker, Douglas G A; Goldberg, Ivan

    2016-01-01

    Accurate measurement of intra-ocular pressure is a fundamental component of the ocular examination. The most common method of measuring IOP is by Goldmann applanation tonometry, the accuracy of which is influenced by the thickness and biomechanical properties of the cornea. Algorithms devised to correct for corneal thickness to estimate IOP oversimplify the effects of corneal biomechanics. The viscous and elastic properties of the cornea influence IOP measurements in unpredictable ways, a finding borne out in studies of patients with inherently abnormal and surgically altered corneal biomechanics. Dynamic contour tonometry, rebound tonometry and the ocular response analyzer provide useful alternatives to GAT in patients with abnormal corneas, such as those who have undergone laser vision correction or keratoplasty. This article reviews the various methods of intra-ocular pressure measurement available to the clinician and the ways in which their utility is influenced by variations in corneal thickness and biomechanics.

  20. Elastic microfibril distribution in the cornea: Differences between normal and keratoconic stroma.

    Science.gov (United States)

    White, Tomas L; Lewis, Philip N; Young, Robert D; Kitazawa, Koji; Inatomi, Tsutomu; Kinoshita, Shigeru; Meek, Keith M

    2017-06-01

    The optical and biomechanical properties of the cornea are largely governed by the collagen-rich stroma, a layer that represents approximately 90% of the total thickness. Within the stroma, the specific arrangement of superimposed lamellae provides the tissue with tensile strength, whilst the spatial arrangement of individual collagen fibrils within the lamellae confers transparency. In keratoconus, this precise stromal arrangement is lost, resulting in ectasia and visual impairment. In the normal cornea, we previously characterised the three-dimensional arrangement of an elastic fiber network spanning the posterior stroma from limbus-to-limbus. In the peripheral cornea/limbus there are elastin-containing sheets or broad fibers, most of which become microfibril bundles (MBs) with little or no elastin component when reaching the central cornea. The purpose of the current study was to compare this network with the elastic fiber distribution in post-surgical keratoconic corneal buttons, using serial block face scanning electron microscopy and transmission electron microscopy. We have demonstrated that the MB distribution is very different in keratoconus. MBs are absent from a region of stroma anterior to Descemet's membrane, an area that is densely populated in normal cornea, whilst being concentrated below the epithelium, an area in which they are absent in normal cornea. We contend that these latter microfibrils are produced as a biomechanical response to provide additional strength to the anterior stroma in order to prevent tissue rupture at the apex of the cone. A lack of MBs anterior to Descemet's membrane in keratoconus would alter the biomechanical properties of the tissue, potentially contributing to the pathogenesis of the disease. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Differentially expressed wound healing-related microRNAs in the human diabetic cornea.

    Science.gov (United States)

    Funari, Vincent A; Winkler, Michael; Brown, Jordan; Dimitrijevich, Slobodan D; Ljubimov, Alexander V; Saghizadeh, Mehrnoosh

    2013-01-01

    MicroRNAs are powerful gene expression regulators, but their corneal repertoire and potential changes in corneal diseases remain unknown. Our purpose was to identify miRNAs altered in the human diabetic cornea by microarray analysis, and to examine their effects on wound healing in cultured telomerase-immortalized human corneal epithelial cells (HCEC) in vitro. Total RNA was extracted from age-matched human autopsy normal (n=6) and diabetic (n=6) central corneas, Flash Tag end-labeled, and hybridized to Affymetrix® GeneChip® miRNA Arrays. Select miRNAs associated with diabetic cornea were validated by quantitative RT-PCR (Q-PCR) and by in situ hybridization (ISH) in independent samples. HCEC were transfected with human pre-miR™miRNA precursors (h-miR) or their inhibitors (antagomirs) using Lipofectamine 2000. Confluent transfected cultures were scratch-wounded with P200 pipette tip. Wound closure was monitored by digital photography. Expression of signaling proteins was detected by immunostaining and Western blot. Using microarrays, 29 miRNAs were identified as differentially expressed in diabetic samples. Two miRNA candidates showing the highest fold increased in expression in the diabetic cornea were confirmed by Q-PCR and further characterized. HCEC transfection with h-miR-146a or h-miR-424 significantly retarded wound closure, but their respective antagomirs significantly enhanced wound healing vs. controls. Cells treated with h-miR-146a or h-miR-424 had decreased p-p38 and p-EGFR staining, but these increased over control levels close to the wound edge upon antagomir treatment. In conclusion, several miRNAs with increased expression in human diabetic central corneas were found. Two such miRNAs inhibited cultured corneal epithelial cell wound healing. Dysregulation of miRNA expression in human diabetic cornea may be an important mediator of abnormal wound healing.

  2. Differentially expressed wound healing-related microRNAs in the human diabetic cornea.

    Directory of Open Access Journals (Sweden)

    Vincent A Funari

    Full Text Available MicroRNAs are powerful gene expression regulators, but their corneal repertoire and potential changes in corneal diseases remain unknown. Our purpose was to identify miRNAs altered in the human diabetic cornea by microarray analysis, and to examine their effects on wound healing in cultured telomerase-immortalized human corneal epithelial cells (HCEC in vitro. Total RNA was extracted from age-matched human autopsy normal (n=6 and diabetic (n=6 central corneas, Flash Tag end-labeled, and hybridized to Affymetrix® GeneChip® miRNA Arrays. Select miRNAs associated with diabetic cornea were validated by quantitative RT-PCR (Q-PCR and by in situ hybridization (ISH in independent samples. HCEC were transfected with human pre-miR™miRNA precursors (h-miR or their inhibitors (antagomirs using Lipofectamine 2000. Confluent transfected cultures were scratch-wounded with P200 pipette tip. Wound closure was monitored by digital photography. Expression of signaling proteins was detected by immunostaining and Western blot. Using microarrays, 29 miRNAs were identified as differentially expressed in diabetic samples. Two miRNA candidates showing the highest fold increased in expression in the diabetic cornea were confirmed by Q-PCR and further characterized. HCEC transfection with h-miR-146a or h-miR-424 significantly retarded wound closure, but their respective antagomirs significantly enhanced wound healing vs. controls. Cells treated with h-miR-146a or h-miR-424 had decreased p-p38 and p-EGFR staining, but these increased over control levels close to the wound edge upon antagomir treatment. In conclusion, several miRNAs with increased expression in human diabetic central corneas were found. Two such miRNAs inhibited cultured corneal epithelial cell wound healing. Dysregulation of miRNA expression in human diabetic cornea may be an important mediator of abnormal wound healing.

  3. Effect of glaucoma tube shunt parameters on cornea endothelial cells in patients with Ahmed valve implants.

    Science.gov (United States)

    Koo, Euna B; Hou, Jing; Han, Ying; Keenan, Jeremy D; Stamper, Robert L; Jeng, Bennie H

    2015-01-01

    The aim of this study was to assess the effect of various tube parameters on corneal endothelial cell density (ECD) after insertion of Ahmed valves. Thirty-nine eyes of 33 patients with previous superotemporal (ST) Ahmed valve implantation and 20 eyes of 13 participants with previous uncomplicated phacoemulsification and intraocular lens implantation but no history of glaucoma surgery were evaluated. Various tube parameters were measured with anterior segment optical coherence tomography. ST, central, and inferonasal (IN) ECD and pachymetry were measured. Endothelial cell loss and corneal thickness in the ST cornea was compared with those in the IN cornea. The mean age of the operated patients was 58 ± 22 years, and the mean time since glaucoma surgery was 2.5 ± 2.6 years. Thirty-two of the 39 study eyes were pseudophakic. The ECD was significantly lower in the ST endothelium than in the IN endothelium in eyes with glaucoma tube surgery (P < 0.001), although this relative reduction in ST ECD was not greater than that seen in pseudophakic control eyes (P = 0.16). In univariate analysis, tube angle relative to the cornea and distance from the tip of the tube to the cornea were significant risk factors for decreased ST endothelial cell loss when assessed relative to the IN ECD (P = 0.01 and P = 0.02, respectively). In multivariate analysis, only the distance of the tube tip to the cornea remained significantly associated with ST endothelial cell loss. Although this was a retrospective study with inherent limitations, tubes that are closer to the cornea seem to lead to increased loss of adjacent endothelial cells.

  4. [Cornea bank of Lyon: from quality diagnosis to ISO 9001 certification].

    Science.gov (United States)

    Pascal, P; Chalochet, A; Damour, O

    2001-12-01

    The tissue and cell bank of the HCL (Hospices Civils de Lyon) has, since 10 June 1999, consisted of two sections with related activities: cell culture for the Skin Substitutes Laboratory (Laboratoire des Substituts Cutanés, LSC) and preservation of corneas at 31 degrees C for the Cornea Bank. As the LSC had been ISO 9001 certified since March 1997 our aim, since merger, was to raise the Cornea Bank to the same level of quality as the LSC, so as to coincide with the renewal of the LSC certificate in February 2000. The methods we used (project, quality control, analysis and process optimization) led us to receive official certification only nine months after the merger. The procedure started with a program of quality control at the Cornea Bank from February 1999 onwards, in order to list the work and equipment required, evaluate its documentation system and what was needed to incorporate this new activity into the existing system of quality assurance at the LSC. On the 7th March 2000, the Tissue and Cell Bank of the HCL obtained an ISO 9001 certificate for its combined functions. As well as achieving our objectives and the strong points highlighted by the auditor during the renewal process, this quality assessment revealed many advantages: improvements in the conservation of corneas, economies in staff replacement and reductions in both the cost of maintaining quality, the cost of the corneas themselves, etc. The decree 'Banque' no. 99-741 of 30th August 1999, which put in place the system of authorization of tissue banks in France, demands quality control. Our application for certification which started in early 1999 had anticipated this regulation. This helped us enormously when compiling the dossier accompanying the official request and was an essential element in obtaining the favourable response of the ASSAPS on 21 June 2000.

  5. Translocations affecting human immunoglobulin heavy chain locus

    Directory of Open Access Journals (Sweden)

    Sklyar I. V.

    2014-03-01

    Full Text Available Translocations involving human immunoglobulin heavy chain (IGH locus are implicated in different leukaemias and lymphomas, including multiple myeloma, mantle cell lymphoma, Burkitt’s lymphoma and diffuse large B cell lymphoma. We have analysed published data and identified eleven breakpoint cluster regions (bcr related to these cancers within the IgH locus. These ~1 kbp bcrs are specific for one or several types of blood cancer. Our findings could help devise PCR-based assays to detect cancer-related translocations, to identify the mechanisms of translocations and to help in the research of potential translocation partners of the immunoglobulin locus at different stages of B-cell differentiation.

  6. Multiparameter thermo-mechanical OCT-based characterization of laser-induced cornea reshaping

    Science.gov (United States)

    Zaitsev, Vladimir Yu.; Matveyev, Alexandr L.; Matveev, Lev A.; Gelikonov, Grigory V.; Vitkin, Alex; Omelchenko, Alexander I.; Baum, Olga I.; Shabanov, Dmitry V.; Sovetsky, Alexander A.; Sobol, Emil N.

    2017-02-01

    Phase-sensitive optical coherence tomography (OCT) is used for visualizing dynamic and cumulative strains and corneashape changes during laser-produced tissue heating. Such non-destructive (non-ablative) cornea reshaping can be used as a basis of emerging technologies of laser vision correction. In experiments with cartilaginous samples, polyacrilamide phantoms and excised rabbit eyes we demonstrate ability of the developed OCT system to simultaneously characterize transient and cumulated strain distributions, surface displacements, scattering tissue properties and possibility of temperature estimation via thermal-expansion measurements. The proposed approach can be implemented in perspective real-time OCT systems for ensuring safety of new methods of laser reshaping of cornea.

  7. Surveillance of Vittaforma corneae in hot springs by a small-volume procedure.

    Science.gov (United States)

    Chen, Jung-Sheng; Hsu, Tsui-Kang; Hsu, Bing-Mu; Huang, Tung-Yi; Huang, Yu-Li; Shaio, Men-Fang; Ji, Dar-Der

    2017-07-01

    Vittaforma corneae is an obligate intracellular fungus and can cause human ocular microsporidiosis. Although accumulating reports of V. corneae causing keratoconjunctivitis in both healthy and immunocompromised persons have been published, little is known about the organism's occurrence in aquatic environments. Limitations in detection sensitivity have meant a large sampling volume is required to detect the pathogen up to now, which is problematic. A recent study in Taiwan has shown that some individuals suffering from microsporidial keratitis (MK) were infected after exposure to the pathogen at a hot spring. As a consequence of this, a survey and analysis of environmental V. corneae present in hot springs became an urgent need. In this study, sixty water samples from six hot spring recreation areas around Taiwan were analyzed. One liter of water from each sample site was filtered to harvest the fungi. The positive samples were detected using a modified nested PCR approach followed by sequencing using specific SSU rRNA gene primer pairs for V. corneae. In total fifteen V. corneae-like isolates were identified (25.0% of sites). Among them, six isolates, which were collected from recreational areas B, C and D, were highly similar to known V. corneae keratitis strains from Taiwan and other countries. Furthermore, five isolates, which were collected from recreation areas A, C, E and F, were very similar to Vittaforma-like diarrhea strains isolated in Portugal. Cold spring water tubs and public foot bath pools had the highest detection rate (50%), suggesting that hot springs might be contaminated via untreated water sources. Comparing the detection rate across different regions of Taiwan, Taitung, which is in the east of the island, gave the highest positive rate (37.5%). Statistical analysis showed that outdoor/soil exposure and a high heterotrophic plate count (HPC) were risk factors for the occurrence of V. corneae. Our findings provide empirical evidence

  8. Experience of Comamonas acidovorans keratitis with delayed onset and treatment response in immunocompromised cornea.

    Science.gov (United States)

    Lee, Sang Mok; Kim, Mee Kum; Lee, Jae Lim; Wee, Won Ryang; Lee, Jin Hak

    2008-03-01

    To report 2 cases of Comamonas acidovorans keratitis in immunocompromised cornea. A complete review of the medical records of the two cases of Comamonas acidovorans keratitis. We found some similarities in clinical courses of two cases. Both of them showed development of keratitis during the management with corticosteroids, delayed onset, slow response to antibiotics, and relatively less affected corneal epithelium. Comamonas acidovorans is known as a less virulent organism. However it can cause an indolent infection that responds slowly even to adequate antibiotics therapy in immunocompromised corneas.

  9. Computer driven optical keratometer and method of evaluating the shape of the cornea

    Science.gov (United States)

    Baroth, Edmund C. (Inventor); Mouneimme, Samih A. (Inventor)

    1994-01-01

    An apparatus and method for measuring the shape of the cornea utilize only one reticle to generate a pattern of rings projected onto the surface of a subject's eye. The reflected pattern is focused onto an imaging device such as a video camera and a computer compares the reflected pattern with a reference pattern stored in the computer's memory. The differences between the reflected and stored patterns are used to calculate the deformation of the cornea which may be useful for pre-and post-operative evaluation of the eye by surgeons.

  10. Optical properties of an anterior lamellar human cornea model based on fibrin-agarose

    Science.gov (United States)

    Ionescu, Ana M.; Cardona, Juan de la Cruz; Ghinea, Razvan; Garzón, Ingrid; González-Andrades, Miguel; Alaminos, Miguel; Pérez, Maria del Mar

    2017-08-01

    The optical evaluation carried out using the Inverse Adding-Doubling (IAD) method to determine the scattering and the absorption coefficients of the bioengineered human corneal stromas showed that this type of artificial biomaterials shared many similarities with native control cornea after four weeks of development in culture. Their absorption and reduced scattering coefficients values were higher than the ones of the control cornea, but their spectral behaviors of both coefficients were similar. Time of development in culture was an influencing factor on the results.

  11. Removal of a barbed fish hook from the cornea of an 8-year-old boy.

    Science.gov (United States)

    Kemp, Pavlina S; Shah, Ankoor S; Elliott, Alexandra T; Wan, Michael J

    2017-10-01

    This video article shows the surgical removal of a three-pronged barbed fish hook from the cornea and anterior chamber of an 8-year-old boy. The advance-and-cut method is shown: the embedded barbed point of the fish hook was advanced through the cornea, its point was cut off, and the shank of the hook was withdrawn. This method was chosen due to the three-pronged configuration of the fish hook to minimize additional trauma to the eye. Other methods of fish hook removal are briefly reviewed. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

  12. Optics of the human cornea influence the accuracy of stereo eye-tracking methods: a simulation study

    NARCIS (Netherlands)

    Barsingerhorn, A.D.; Boonstra, F.N.; Goossens, H.H.L.M.

    2017-01-01

    Current stereo eye-tracking methods model the cornea as a sphere with one refractive surface. However, the human cornea is slightly aspheric and has two refractive surfaces. Here we used ray-tracing and the Navarro eye-model to study how these optical properties affect the accuracy of different

  13. Culture, gender and locus of control

    DEFF Research Database (Denmark)

    Ottsen, Christina Lundsgaard; Johannessen, Kim Berg; Berntsen, Dorthe

    The current study is a cross-cultural comparison between the Middle East and Scandinavia. Two societies that offer a unique opportunity to examine gender differences in personal goals and how goals are affected by locus of control.......The current study is a cross-cultural comparison between the Middle East and Scandinavia. Two societies that offer a unique opportunity to examine gender differences in personal goals and how goals are affected by locus of control....

  14. The use of human cornea organotypic cultures to study herpes simplex virus type 1 (HSV-1)-induced inflammation.

    Science.gov (United States)

    Drevets, Peter; Chucair-Elliott, Ana; Shrestha, Priyadarsini; Jinkins, Jeremy; Karamichos, Dimitrios; Carr, Daniel J J

    2015-10-01

    To determine the utility of human organotypic cornea cultures as a model to study herpes simplex virus type 1 (HSV-1)-induced inflammation and neovascularization. Human organotypic cornea cultures were established from corneas with an intact limbus that were retrieved from donated whole globes. One cornea culture was infected with HSV-1 (10(4) plaque-forming units), while the other cornea from the same donor was mock-infected. Supernatants were collected at intervals post-culture with and without infection to determine viral titer (by plaque assay) and pro-angiogenic and proinflammatory cytokine concentration by suspension array analysis. In some experiments, the cultured corneas were collected and evaluated for HSV-1 antigens by immunohistochemical means. Another set of experiments measured susceptibility of human three-dimensional cornea fibroblast constructs, in the presence and absence of TGF-β1, to HSV-1 infection in terms of viral replication and the inflammatory response to infection as a comparison to the organotypic cornea cultures. Organotypic cornea cultures and three-dimensional fibroblast constructs exhibited varying degrees of susceptibility to HSV-1. Fibroblast constructs were more susceptible to infection in terms of infectious virus recovered in a shorter period of time. There were changes in the levels of select pro-angiogenic or proinflammatory cytokines that were dictated as much by the cultures producing them as by whether they were infected with HSV-1 or treated with TGF-β1. Organotypic cornea and three-dimensional fibroblast cultures are likely useful for the identification and short-term study of novel antiviral compounds and virus replication, but are limited in the study of the local immune response to infection.

  15. Intracellular Position of Centrioles and the Direction of Homeostatic Epithelial Cell Movements in the Mouse Cornea.

    Science.gov (United States)

    Silverman, Erika; Zhao, Jin; Merriam, John C; Nagasaki, Takayuki

    2017-02-01

    Corneal epithelial cells exhibit continuous centripetal movements at a rate of about 30 µm per day, but neither the driving force nor the mechanism that determines the direction of movements is known. To facilitate the investigation of homeostatic cell movement, we examined if the intracellular position of a centriole can be used as a directional marker of epithelial cell movements in the mouse cornea. A direction of cell movements was estimated in fixed specimens from a pattern of underlying subepithelial nerve fibers. Intracellular position of centrioles was determined by gamma-tubulin immunohistology and plotted in a narrow strip along the entire diameter of a cornea from limbus to limbus. When we determined the position of centrioles in the peripheral cornea where cell movements proceed generally along a radial path, about 55% of basal epithelial cells contained a centriole in the front half of a cell. However, in the central cornea where cells exhibit a spiral pattern of movements, centrioles were distributed randomly. These results suggest that centrioles tend to be positioned toward the direction of movement in corneal basal epithelial cells when they are moving centripetally at a steady rate.

  16. Crosslinked collagen-gelatin-hyaluronic acid biomimetic film for cornea tissue engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yang; Ren, Li, E-mail: psliren@scut.edu.cn; Wang, Yingjun, E-mail: imwangyj@163.com

    2013-01-01

    Cornea disease may lead to blindness and keratoplasty is considered as an effective treatment method. However, there is a severe shortage of donor corneas worldwide. This paper presents the crosslinked collagen (Col)-gelatin (Gel)-hyaluronic acid (HA) films developed by making use of 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) as the crosslinker. The test results on the physical and biological properties indicate that the CGH631 film (the mass ratio of Col:Gel:HA = 6:3:1) has appropriate optical performance, hydrophilicity and mechanical properties. The diffusion properties of the CGH631 film to NaCl and tryptophan are also satisfactory and the measured data are 2.43 Multiplication-Sign 10{sup -6} cm{sup 2}/s and 7.97 Multiplication-Sign 10{sup -7} cm{sup 2}/s, respectively. In addition, cell viability studies demonstrate that the CGH631 film has good biocompatibility, on which human corneal epithelial cells attached and proliferated well. This biocompatible film may have potential use in cornea tissue engineering. - Highlights: Black-Right-Pointing-Pointer Crosslinked collagen-gelatin-hyaluronic acid films were fabricated in this study. Black-Right-Pointing-Pointer The film had appropriate physical properties. Black-Right-Pointing-Pointer Diffusion coefficient of the film was comparable with the human cornea. Black-Right-Pointing-Pointer HCEC viability studies confirmed the biocompatibility of the film.

  17. Pathways and Mechanisms Underlying the Photophysics and Photochemistry of Riboflavin induced cornea crosslinking

    DEFF Research Database (Denmark)

    Breitenbach, Thomas; Ogilby, Peter Remsen

    In this talk, we will describe general pathways involved in the photophysics of a photosensitized process, which can lead to crosslinking due to light excitation of Riboflavin in the cornea. Furthermore, we will elucidate different aspects of reactions that can produce crosslinks, with respect...

  18. High-resolution, label-free two-photon imaging of diseased human corneas

    Science.gov (United States)

    Batista, Ana; Breunig, Hans Georg; König, Aisada; Schindele, Andreas; Hager, Tobias; Seitz, Berthold; König, Karsten

    2018-03-01

    The diagnosis of corneal diseases may be improved by monitoring the metabolism of cells and the structural organization of the stroma using two-photon imaging (TPI). We used TPI to assess the differences between nonpathological (NP) human corneas and corneas diagnosed with either keratoconus, Acanthamoeba keratitis, or stromal corneal scars. Images were acquired using a custom-built five-dimensional laser-scanning microscope with a broadband sub-15 femtosecond near-infrared pulsed excitation laser and a 16-channel photomultiplier tube detector in combination with a time-correlated single photon counting module. Morphological alterations of epithelial cells were observed for all pathologies. Moreover, diseased corneas showed alterations to the cells' metabolism that were revealed using the NAD(P)H free to protein-bound ratios. The mean autofluorescence lifetime of the stroma and the organization of the collagen fibers were also significantly altered due to the pathologies. We demonstrate that TPI can be used to distinguish between NP and diseased human corneas, based not only on alterations of the cells' morphology, which can also be evaluated using current clinical devices, but on additional morphological and functional features such as the organization of the stroma and the cells' metabolism. Therefore, TPI could become an efficient tool for diagnosing corneal diseases and better understanding the biological processes of the diseases.

  19. [Current approaches to evaluating the anatomic and functional status of the cornea].

    Science.gov (United States)

    Avetisov, S E; Borodina, N V; Kobzova, M V; Musaeva, G M

    2010-01-01

    The review provides data on current methods for evaluating the anatomic and functional status of the cornea (light refraction, light transmission, and biomechanical properties, in particular). It analyzes the main advantages and disadvantages of basic (biomicroscopy, endothelial microscopy, ophthalmometry, topography, and pachymetry) and special (confocal microscopy, optical coherence tomography, ultrasound biomicroscopy, aberrometry, bidirectional corneal applanation, and keratoesthesiometry) studies.

  20. Wavelength-dependent ultraviolet induction of cyclobutane pyrimidine dimers in the human cornea.

    Science.gov (United States)

    Mallet, Justin D; Rochette, Patrick J

    2013-08-01

    Exposition to ultraviolet (UV) light is involved in the initiation and the progression of skin cancer. The genotoxicity of UV light is mainly attributed to the induction of cyclobutane pyrimidine dimers (CPDs), the most abundant DNA damage generated by all UV types (UVA, B and C). The human cornea is also exposed to the harmful UV radiations, but no UV-related neoplasm has been reported in this ocular structure. The probability that a specific DNA damage leads to a mutation and eventually to cellular transformation is influenced by its formation frequency. To shed light on the genotoxic effect of sunlight in the human eye, we have analyzed CPD induction in the cornea and the iris following irradiation of ex vivo human eyes with UVA, B or C. The extent of CPD induction was used to establish the penetrance of the different UV types in the human cornea. We show that UVB- and UVC-induced CPDs are concentrated in the corneal epithelium and do not penetrate deeply beyond this corneal layer. On the other hand, UVA wavelengths penetrate deeper and induce CPDs in the entire cornea and in the first layers of the iris. Taken together, our results are undoubtedly an important step towards better understanding the consequences of UV exposure to the human eye.

  1. Crosslinked collagen–gelatin–hyaluronic acid biomimetic film for cornea tissue engineering applications

    International Nuclear Information System (INIS)

    Liu, Yang; Ren, Li; Wang, Yingjun

    2013-01-01

    Cornea disease may lead to blindness and keratoplasty is considered as an effective treatment method. However, there is a severe shortage of donor corneas worldwide. This paper presents the crosslinked collagen (Col)–gelatin (Gel)–hyaluronic acid (HA) films developed by making use of 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) as the crosslinker. The test results on the physical and biological properties indicate that the CGH631 film (the mass ratio of Col:Gel:HA = 6:3:1) has appropriate optical performance, hydrophilicity and mechanical properties. The diffusion properties of the CGH631 film to NaCl and tryptophan are also satisfactory and the measured data are 2.43 × 10 −6 cm 2 /s and 7.97 × 10 −7 cm 2 /s, respectively. In addition, cell viability studies demonstrate that the CGH631 film has good biocompatibility, on which human corneal epithelial cells attached and proliferated well. This biocompatible film may have potential use in cornea tissue engineering. - Highlights: ► Crosslinked collagen–gelatin–hyaluronic acid films were fabricated in this study. ► The film had appropriate physical properties. ► Diffusion coefficient of the film was comparable with the human cornea. ► HCEC viability studies confirmed the biocompatibility of the film.

  2. Eye evolution: lens and cornea as an upgrade of animal visual system

    Czech Academy of Sciences Publication Activity Database

    Jonášová, Kristýna; Kozmik, Zbyněk

    2008-01-01

    Roč. 19, č. 2 (2008), s. 71-81 ISSN 1084-9521 R&D Projects: GA AV ČR IAA500520604; GA MŠk(CZ) 1M0520 Institutional research plan: CEZ:AV0Z50520514 Keywords : eye * lens * cornea Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.528, year: 2008

  3. Effect of irradiation and cystamine on the secondary induction of cornea in anura larvae

    International Nuclear Information System (INIS)

    Popov, D.V.; Starodubov, S.M.

    1977-01-01

    Secondary induction of cornea in the transplanted skin has been studied in amphibian larvae after the effect of irradiation and cystamine on the recipients and donors. Comparison of the results obtained with those reported earlier has demonstrated that the irradiated tissue is more responsive to inductive effects than the intact one

  4. Ex vivo rabbit cornea diffusion studies with a soluble insert of moxifloxacin.

    Science.gov (United States)

    Sebastián-Morelló, María; Calatayud-Pascual, María Aracely; Rodilla, Vicent; Balaguer-Fernández, Cristina; López-Castellano, Alicia

    2018-02-01

    The objective of this research was to develop and evaluate an ocular insert for the controlled drug delivery of moxifloxacin which could perhaps be used in the treatment of corneal keratitis or even bacterial endophthalmitis. We have evaluated the ex vivo ocular diffusion of moxifloxacin through rabbit cornea, both fresh and preserved under different conditions. Histological studies were also carried out. Subsequently, drug matrix inserts were prepared using bioadhesive polymers. The inserts were evaluated for their physicochemical parameters. Ophthalmic ex vivo permeation of moxifloxacin was carried out with the most promising insert. The formulate insert was thin and provided higher ocular diffusion than commercial formulations. Ocular diffusion studies revealed significant differences between fresh and frozen corneas. Histological examinations also showed differences in the thickness of stroma between fresh and frozen corneas. The ophthalmic insert we have developed allows a larger quantity of moxifloxacin to permeate through the cornea than existing commercial formulations of the drug. Ocular delivery of moxifloxacin with this insert could be a new approach for the treatment of eye diseases.

  5. Measurement of locus copy number by hybridisation with amplifiable probes

    Science.gov (United States)

    Armour, John A. L.; Sismani, Carolina; Patsalis, Philippos C.; Cross, Gareth

    2000-01-01

    Despite its fundamental importance in genome analysis, it is only recently that systematic approaches have been developed to assess copy number at specific genetic loci, or to examine genomic DNA for submicroscopic deletions of unknown location. In this report we show that short probes can be recovered and amplified quantitatively following hybridisation to genomic DNA. This simple observation forms the basis of a new approach to determining locus copy number in complex genomes. The power and specificity of multiplex amplifiable probe hybridisation is demonstrated by the simultaneous assessment of copy number at a set of 40 human loci, including detection of deletions causing Duchenne muscular dystrophy and Prader–Willi/Angelman syndromes. Assembly of other probe sets will allow novel, technically simple approaches to a wide variety of genetic analyses, including the potential for extension to high resolution genome-wide screens for deletions and amplifications. PMID:10606661

  6. Measurement of locus copy number by hybridisation with amplifiable probes.

    Science.gov (United States)

    Armour, J A; Sismani, C; Patsalis, P C; Cross, G

    2000-01-15

    Despite its fundamental importance in genome analysis, it is only recently that systematic approaches have been developed to assess copy number at specific genetic loci, or to examine genomic DNA for submicro-scopic deletions of unknown location. In this report we show that short probes can be recovered and amplified quantitatively following hybridisation to genomic DNA. This simple observation forms the basis of a new approach to determining locus copy number in complex genomes. The power and specificity of multiplex amplifiable probe hybridisation is demonstrated by the simultaneous assessment of copy number at a set of 40 human loci, including detection of deletions causing Duchenne muscular dystrophy and Prader-Willi/Angelman syndromes. Assembly of other probe sets will allow novel, technically simple approaches to a wide variety of genetic analyses, including the potential for extension to high resolution genome-wide screens for deletions and amplifications.

  7. Oxygen transport through soft contact lens and cornea: Lens characterization and metabolic modeling

    Science.gov (United States)

    Chhabra, Mahendra

    The human cornea requires oxygen to sustain metabolic processes critical for its normal functioning. Any restriction to corneal oxygen supply from the external environment (e.g., by wearing a low oxygen-permeability contact lens) can lead to hypoxia, which may cause corneal edema (swelling), limbal hyperemia, neovascularization, and corneal acidosis. The need for adequate oxygen to the cornea is a major driving force for research and development of hypertransmissible soft contact lenses (SCLs). Currently, there is no standard technique for measuring oxygen permeability (Dk) of hypertransmissible silicone-hydrogel SCLs. In this work, an electrochemistry-based polarographic apparatus was designed, built, and operated to measure oxygen permeability in hypertransmissible SCLs. Unlike conventional methods where a range of lens thickness is needed for determining oxygen permeabilities of SCLs, this apparatus requires only a single lens thickness. The single-lens permeameter provides a reliable, efficient, and economic tool for measuring oxygen permeabilities of commercial hypertransmissible SCLs. The single-lens permeameter measures not only the product Dk, but, following modification, it measures separately diffusivity, D, and solubility, k, of oxygen in hypertransmissible SCLs. These properties are critical for designing better lens materials that ensure sufficient oxygen supply to the cornea. Metabolism of oxygen in the cornea is influenced by contact-lens-induced hypoxia, diseases such as diabetes, surgery, and drug treatment, Thus, estimation of the in-vivo corneal oxygen consumption rate is essential for gauging adequate oxygen supply to the cornea. Therefore, we have developed an unsteady-state reactive-diffusion model for the cornea-contact-lens system to determine in-vivo human corneal oxygen-consumption rate. Finally, a metabolic model was developed to determine the relation between contact-lens oxygen transmissibility (Dk/L) and corneal oxygen deficiency. A

  8. Lens regeneration from the cornea requires suppression of Wnt/β-catenin signaling.

    Science.gov (United States)

    Hamilton, Paul W; Sun, Yu; Henry, Jonathan J

    2016-04-01

    The frog, Xenopus laevis, possesses a high capacity to regenerate various larval tissues, including the lens, which is capable of complete regeneration from the cornea epithelium. However, the molecular signaling mechanisms of cornea-lens regeneration are not fully understood. Previous work has implicated the involvement of the Wnt signaling pathway, but molecular studies have been very limited. Iris-derived lens regeneration in the newt (Wolffian lens regeneration) has shown a necessity for active Wnt signaling in order to regenerate a new lens. Here we provide evidence that the Wnt signaling pathway plays a different role in the context of cornea-lens regeneration in Xenopus. We examined the expression of frizzled receptors and wnt ligands in the frog cornea epithelium. Numerous frizzled receptors (fzd1, fzd2, fzd3, fzd4, fzd6, fzd7, fzd8, and fzd10) and wnt ligands (wnt2b.a, wnt3a, wnt4, wnt5a, wnt5b, wnt6, wnt7b, wnt10a, wnt11, and wnt11b) are expressed in the cornea epithelium, demonstrating that this tissue is transcribing many of the ligands and receptors of the Wnt signaling pathway. When compared to flank epithelium, which is lens regeneration incompetent, only wnt11 and wnt11b are different (present only in the cornea epithelium), identifying them as potential regulators of cornea-lens regeneration. To detect changes in canonical Wnt/β-catenin signaling occurring within the cornea epithelium, axin2 expression was measured over the course of regeneration. axin2 is a well-established reporter of active Wnt/β-catenin signaling, and its expression shows a significant decrease at 24 h post-lentectomy. This decrease recovers to normal endogenous levels by 48 h. To test whether this signaling decrease was necessary for lens regeneration to occur, regenerating eyes were treated with either 6-bromoindirubin-3'-oxime (BIO) or 1-azakenpaullone - both activators of Wnt signaling - resulting in a significant reduction in the percentage of cases with successful

  9. Infrared irradiation alters the expression of matrix metalloproteinases and glycosaminoglycans in the cornea and crystalline lens.

    Science.gov (United States)

    Dadoukis, Panagiotis; Klagas, Ioannis; Komnenou, Anastasia; Karakiulakis, George; Karoutis, Athanasios; Karampatakis, Vassilios; Papakonstantinou, Eleni

    2013-08-01

    Prolonged exposure to infrared (IR) radiation is associated with different types of damage to cornea and lens. The aim of our study was to investigate the effect of acute and chronic exposure to IR radiation on the activity of matrix metalloproteinase-2 (MMP-2) and MMP-9 and on the expression of glycosaminoglycans (GAG) in the rabbit cornea and crystalline lens. New Zealand rabbits were subjected to IR radiation for 4 months (chronic exposure to IR) or to normal light (control group). In experiments regarding acute exposure, animals were subjected to IR radiation or normal light for 12 h, in the presence of 0.1% diclofenac sodium (eye drops instilled in the right eye of animals) or saline (instilled in the left eye of animals). The cornea and lens were dissected away and homogenized. The activity of MMP-2 and MMP-9 was assayed by gelatine zymography. Total GAG were isolated from tissue specimens after lipid extraction and extensive digestion with pronase and DNase and characterized by treatment with GAG-degrading enzymes, followed by electrophoresis on cellulose acetate membranes. Acute or chronic exposure to IR radiation induced the activity of MMP-2 in cornea and lens, whereas only acute IR radiation increased the content of heparan sulphate in crystalline lens. Local administration of diclofenac sodium did not prevent the above effects of acute IR radiation. The detrimental effects of excessive or prolonged exposure of the eyes to IR radiation are associated with induced activity of MMP-2 in cornea and lens and alterations in the content of heparan sulphate in lens. Thus, MMP and GAG may offer alternative targets for pharmacological intervention to confront ocular damages associated with IR radiation.

  10. Thermodynamic measurement after cooling the cornea with intact epithelium and lid manipulation.

    Science.gov (United States)

    de Ortueta, Diego; Magnago, Thomas; Arba-Mosquera, Samuel

    2015-01-01

    To characterize the rate of change of ocular surface temperature (OST) under lid manipulation after cooling the intact cornea with balanced salt solution (BSS). In a patient for refractive surgery, prior to the ablation, the temperature of the cornea was continuously recorded with a high speed infrared (350Hz) camera. Two millilitre of chilled BSS with a temperature of 8.6°Celsius (°C) was instilled for about 3s. Using exponential functions, the three contributions have been determined, subjacent corneal layers, environment, and chilled BSS. The mean temperature of the cornea preoperatively was 34.5°C. After applying the chilled BSS the temperature decreased about 14°C down to an OST of 20°C and the time needed afterwards to get the normal (OST) temperature of about 30°C was 40s. Due to the inserted speculum and missing blink, OST did not reach the original OST of 34.5°C and faded at about 32.5°C. According to our best fitted model, absolute value of each contributing component was 31.4°C (subjacent corneal layers), 26.8°C (environment) and 8.6°C (BSS). Applying chilled BSS to the cornea quickly reduces the temperature of the cornea with a thermal relaxation time of 3s and a amplitude decrease of 8.6°C. This together with a relaxation time of 7s for subjacent corneal layers, and 184s for environment after instillation of BSS combined with a well-controlled environment provides a period of 40s of corneal temperature below baseline, which may be of clinical benefit when applying chilled BSS immediately before or immediately after ablation. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  11. Hydration and transparency of the rabbit cornea irradiated with UVB-doses of 0.25 J/cm(2) and 0.5 J/cm(2) compared with equivalent UVB radiation exposure reaching the human cornea from sunlight.

    Science.gov (United States)

    Cejka, Cestmír; Ardan, Taras; Sirc, Jakub; Michálek, Jiří; Beneš, Jiří; Brůnová, Blanka; Rosina, Jozef

    2011-07-01

    Exposure of the cornea to UV radiation from sunlight evokes intraocular inflammation, photokeratitis. Photokeratitis is caused by UVB radiation. It is accompanied by changes of corneal hydration and light absorption. The aim of this study was to examine the effect of two UVB doses on corneal optics in rabbits and to compare these UVB doses with the equivalent exposure of UVB radiation reaching the human cornea from sunlight. Rabbit corneas were irradiated with a daily UVB dose of 0.25 J/cm(2) or 0.5 J/cm(2) for 4 days. One day after finishing the irradiations the rabbits were sacrificed and corneal light absorption measured using our spectrophotometrical method. Corneal hydration was examined using an ultrasonic Pachymeter every experimental day before the irradiation procedure and the last day before sacrificing the animals. Changes in corneal optics appeared after the repeated exposure of the cornea to a UVB dose of 0.25 J/ cm(2) and massively increased after the repeated exposure of the cornea to a UVB dose of 0.5 J/cm(2). The first significant changes in corneal hydration appeared after a single exposure of the cornea to a UVB dose of 0.25 J/cm(2). Changes in corneal hydration appeared after the exposure of the rabbit cornea to a single UVB dose equivalent to 2.6 hours of solar UVB radiation reaching the human cornea, as measured by UVB sensors embedded in the eyes of mannequin heads facing the sun on a beach at noon in July. Repeated exposure of the rabbit cornea to the same UVB dose evoked profound changes in corneal optics. Although comparison of experimental and outdoor conditions are only approximate, the results in rabbits point to the danger for the human eye from UVB radiation when short stays in sunlight are repeated for several consecutive days without UV protection.

  12. A Danish family with dominant deafness-onychodystrophy syndrome

    DEFF Research Database (Denmark)

    Vind-Kezunovic, Dina; Torring, Pernille M

    2013-01-01

    The rare hereditary disorder "dominant deafness and onychodystrophy (DDOD) syndrome" (OMIM 124480) has been described in a few case reports. No putative DDOD gene or locus has been mapped and the cause of the disorder remains unknown.......The rare hereditary disorder "dominant deafness and onychodystrophy (DDOD) syndrome" (OMIM 124480) has been described in a few case reports. No putative DDOD gene or locus has been mapped and the cause of the disorder remains unknown....

  13. Low-dose radiation effects on the evolution of chronic dystrophical processes in cornea and clouding of crystalline lens

    International Nuclear Information System (INIS)

    Gajdaj, Yu.V.; Gajdaj, V.M.

    1993-01-01

    Low-dose radiation effects on the course of chronic dystrophical processes in cornea and the dynamics of crystalline lens clouding of involution age genesis are investigated in the patients participated in Chernobyl accident response. Examples of the concrete pathological cases are considered. It was stated that the above dose effects led to exacerbation of the chronic slack dystrophical processes in cornea and intensification of the development of cornea primary dystrophy. In a number of cases the intensification of development of crystalline lens clouding takes place resulted in the cataract for 2-3 years

  14. Differential expression and processing of transforming growth factor beta induced protein (TGFBIp) in the normal human cornea during postnatal development and aging

    DEFF Research Database (Denmark)

    Karring, Henrik; Runager, Kasper; Valnickova, Zuzana

    2010-01-01

    Transforming growth factor beta induced protein (TGFBIp, also named keratoepithelin) is an extracellular matrix protein abundant in the cornea. The purpose of this study was to determine the expression and processing of TGFBIp in the normal human cornea during postnatal development and aging...... trimming events from the N-terminus of mature TGFBIp generate TGFBIp isoforms which form a similar "zig-zag" pattern when separated by 2-D polyacrylamide gel electrophoresis (PAGE). This study shows that in humans TGFBIp is more abundant in mature corneas than in the developing cornea...... and that the processing of TGFBIp changes during postnatal development of the cornea. In addition, TGFBIp appears to be degraded in a highly orchestrated manner in the normal human cornea with the resulting C-terminal fragments being retained in the cornea. The age-related changes in the expression and processing...

  15. Efficacious and safe tissue-selective controlled gene therapy approaches for the cornea.

    Directory of Open Access Journals (Sweden)

    Rajiv R Mohan

    2011-04-01

    Full Text Available Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study aimed to define efficient and safe tissue-selective targeted gene therapy approaches for delivering genes into keratocytes of the cornea in vivo using a normal or diseased rabbit model. New Zealand White rabbits, adeno-associated virus serotype 5 (AAV5, and a minimally invasive hair-dryer based vector-delivery technique were used. Fifty microliters of AAV5 titer (6.5×10(12 vg/ml expressing green fluorescent protein gene (GFP was topically applied onto normal or diseased (fibrotic or neovascularized rabbit corneas for 2-minutes with a custom vector-delivery technique. Corneal fibrosis and neovascularization in rabbit eyes were induced with photorefractive keratectomy using excimer laser and VEGF (630 ng using micropocket assay, respectively. Slit-lamp biomicroscopy and immunocytochemistry were used to confirm fibrosis and neovascularization in rabbit corneas. The levels, location and duration of delivered-GFP gene expression in the rabbit stroma were measured with immunocytochemistry and/or western blotting. Slot-blot measured delivered-GFP gene copy number. Confocal microscopy performed in whole-mounts of cornea and thick corneal sections determined geometric and spatial localization of delivered-GFP in three-dimensional arrangement. AAV5 toxicity and safety were evaluated with clinical eye exam, stereomicroscopy, slit-lamp biomicroscopy, and H&E staining. A single 2-minute AAV5 topical application via custom delivery-technique efficiently and selectively transduced keratocytes in the anterior stroma of normal and diseased rabbit corneas as evident from immunocytochemistry and confocal microscopy. Transgene expression was first detected at day 3, peaked at day 7, and was maintained up to 16 weeks (longest tested time point. Clinical and slit-lamp eye examination in live rabbits and H&E staining did not reveal any significant changes between AAV5

  16. Locus of control in relation to flow

    Directory of Open Access Journals (Sweden)

    Celeste M Taylor

    2006-04-01

    Full Text Available The principal objective of the study was to examine the relationship between locus of control and optimal experience (flow in carrying out work and/or study activities. Two questionnaires measuring the aforementioned constructs were administered to a group of first and second-year Human Resource Management students (n=168 between the ages of 16 and 30. The results suggest that more frequent experience of flow is positively correlated with Autonomy and Internal Locus of Control. Limitations, lines of future research, implications and further contributions are discussed.

  17. Exploration of alternative test methods to evaluate phototoxicity of ophthalmic agents by using Statens Seruminstitut Rabbit Cornea cell lines and 3D human reconstituted cornea models.

    Directory of Open Access Journals (Sweden)

    Soyoung Kim

    Full Text Available Many chemicals have been reported to induce phototoxicity. The absorbance of light energy within the sunlight range is a common characteristic of phototoxicity. The 3T3 NRU phototoxicity test (PT in 3T3 mouse skin fibroblasts has been used to identify the phototoxic potential induced by excited chemicals after exposure to ultra violet (UV. However, as phototoxicity may occur in ocular cells, it is necessary to develop a more suitable test for cornea-derived cells. In this study, we attempted to establish a new in vitro PT method in rabbit corneal cell lines (SIRC. We evaluated five ophthalmic agents, ciprofloxacin, levofloxacin, lomefloxacin, norfloxacin, and tetracycline, for their cytotoxic potential and in vitro phototoxicity. The results obtained using 3D human corneal models revealed that the UV-induced eye tissue toxicity by the test substances showed good correlation with those obtained using the in vitro phototoxicity test. However, the results from the 3D PT for ciprofloxacin, norfloxacin, and tetracycline in the 3D human cornea model were only partially comparable. Therefore, we suggest the SIRC cell line as a new phototoxicity test model; however, a sequential testing strategy, such as 3D PT, was also proposed to obtain relevant information for topical eye agents.

  18. Entertainment-education and recruitment of cornea donors: the role of emotion and issue involvement.

    Science.gov (United States)

    Bae, Hyuhn-Suhck

    2008-01-01

    This study examined the role of emotional responses and viewer's level of issue involvement to an entertainment-education show about cornea donation in order to predict intention to register as cornea donors. Results confirmed that sympathy and empathy responses operated as a catalyst for issue involvement, which emerged as an important intermediary in the persuasion process. Issue involvement also was found to be a common causal antecedent of attitude, subjective norm, and perceived behavioral control, the last two of which predict intentions unlike attitude, which does not. The revised path model confirmed that involvement directly influences intention. The findings of this study suggest that adding emotion and involvement in the Theory of Planned Behavior (TPB) enhances the explanatory power of the theory in predicting intentions, which indicates the possibility of combining the Elaboration Likelihood Model (ELM) and the TPB in the prediction of human behaviors.

  19. [Evaluation of Iris Morphology Viewed through Stromal Edematous Corneas by Infrared Camera].

    Science.gov (United States)

    Kobayashi, Masaaki; Morishige, Naoyuki; Morita, Yukiko; Yamada, Naoyuki; Kobayashi, Motomi; Sonoda, Koh-Hei

    2016-02-01

    We reported that the application of infrared camera enables us to observe iris morphology in Peters' anomaly through edematous corneas. To observe the iris morphology in bullous keratopathy or failure grafts with an infrared camera. Eleven bullous keratopathy or failure grafts subjects (6 men and 5 women, mean age ± SD; 72.7 ± 13.0 years old) were enrolled in this study. The iris morphology was observed by applying visible light mode and near infrared light mode of infrared camera (MeibomPen). The detectability of pupil shapes, iris patterns and presence of iridectomy was evaluated. Infrared mode observation enabled us to detect the pupil shapes in 11 out of 11 cases, iris patterns in 3 out of 11 cases, and presence of iridetomy in 9 out of 11 cases although visible light mode observation could not detect any iris morphological changes. Applying infrared optics was valuable for observation of the iris morphology through stromal edematous corneas.

  20. [Biological availability of ophthalmic drugs. 1. Increasing drug permeability in the cornea].

    Science.gov (United States)

    Masteiková, R; Chalupová, Z; Savickiene, N

    2004-03-01

    Most eye diseases are treated by topical administration of ophthalmic preparations. Low ophthalmic bioavailability is due to a number of physiological and physicochemical factors. The main obstacle to the penetration of active ingredients to the eye is the layered character of the cornea. Formulation of ophthalmic preparations enabling easier penetration of this biological barrier thus ranks among the most effective ways of improving bioavailability. Penetrability of the cornea can be increased by the following methods: a) adjustment of the actual acidity in such a way that pH of the preparation makes it possible to produce the optimal portion of non-ionized particles; b) incorporation of absorption enhancers (non-ionic tensides, salts of bile acids, some antimicrobial substances, EDTA, cyclodextrins, etc.) into the composition of the preparation, and c) production of prodrugs or ionic pairs.

  1. Expression profiles of aquaporins in rat conjunctiva, cornea, lacrimal gland and Meibomian gland.

    Science.gov (United States)

    Yu, Dongfang; Thelin, William R; Randell, Scott H; Boucher, Richard C

    2012-10-01

    The aim of the study was to elucidate aquaporin (AQP) family member mRNA expression and protein expression/localization in the rat lacrimal functional unit. The mRNA expression of all rat AQPs (AQP0-9, 11-12) in palpebral, fornical, and bulbar conjunctiva, cornea, lacrimal gland, and Meibomian gland was measured by Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) and real time RT-PCR. Antibodies against AQP1, 3, 4, 5, 9, and 11 were used in Western blotting and immunohistochemistry to determine protein expression and distribution. Our study demonstrated characteristic AQP expression profiles in rat ocular tissues. AQP1, 3, 4, 5, 8, 9, 11, and 12 mRNA were detected in conjunctiva. AQP0, 1, 2, 3, 4, 5, 6, 11, and 12 mRNA were expressed in cornea. AQP0, 1, 2, 3, 4, 5, 7, 8, and 11 mRNA were detected in lacrimal gland. AQP1, 3, 4, 5, 7, 8, 9, 11, and 12 mRNA were identified in Meibomian gland. By Western blot, AQP1, 3, 5, and 11 were detected in conjunctiva; AQP1, 3, 5, and 11 were identified in cornea; AQP1, 3, 4, 5, and 11 were detected in lacrimal gland; and AQP1, 3, 4, 5, 9, and 11 were present in Meibomian gland. Immunohistochemistry localized AQPs to distinct sites in the various tissues. This study rigorously analyzed AQPs expression and localization in rat conjunctiva, cornea, lacrimal gland, and Meibomian gland tissues. Our findings provide a comprehensive platform for further investigation into the physiological or pathophysiological relevance of AQPs in ocular surface. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Finite element analysis of blunt foreign body impact on the cornea after PRK and LASIK.

    Science.gov (United States)

    Mousavi, Seyed Jamaleddin; Nassiri, Nariman; Masoumi, Nafiseh; Nassiri, Nader; Majdi-N, Mercede; Farzaneh, Solmaz; Djalilian, Ali R; Peyman, Gholam A

    2012-01-01

    To investigate the effect of blunt foreign body impact on a human cornea after photorefractive keratectomy (PRK) and LASIK using a simulation model. Computational simulations were performed using a finite element analysis program (LS-Dyna, Livermore Software Technology Corp). The blunt foreign body was set to impact at the center of the corneal surface models (after PRK and LASIK) with thicknesses of 500, 450, 400, 350, and 300 μm. Corneal rupture was assumed to occur at a peak stress of 9.45 MPa and at a strain of 18%. The foreign body projectile was blunt in shape, made from aluminum, contained plastic-kinematic properties, and had a density of 2700 kg/m(3). The projectile was launched at the center of the cornea with velocities ranging from 20 to 60 m/s. The threshold of impact velocities creating rupture in corneal thicknesses of 500, 450, 400, 350, and 300 μm were 33, 32.8, 30.7, 27.9, and 22.8 m/s, respectively, in the PRK model. In the LASIK model, the thresholds creating rupture in the stromal bed of the corneas with thicknesses of 500, 450, 400, 350, and 300 μm were 40, 38.1, 35.6, 31.5, and 26.7 m/s, respectively. The 110-μm corneal flap in the LASIK model ruptured at all velocities. Ruptures occurred at lower velocities in the PRK cornea model than in the corneal stromal bed of the LASIK model following blunt foreign body impact. Copyright 2012, SLACK Incorporated.

  3. Clinical characteristics of keratoconus patients in Malaysia: a review from a cornea specialist centre

    OpenAIRE

    Mohd-Ali, Bariah; Abdu, Mustafa; Yaw, Choong Yean; Mohidin, Norhani

    2012-01-01

    Purpose: To evaluate the demographic profile, refraction, visual acuity (VA), corneal curvature (K) and severity of keratoconus (KC) patients from a cornea specialist centre in Malaysia. This may improve the management of KC patients in this country. Methods: Records of 13,000 patients were reviewed. The patients were categorized into 4 age groups: (Gp 1: 42 years). Refraction and VA were determined using subjective refraction and Snellen chart. Corneal curvature was measured using Orbscan...

  4. Tracing the fate of limbal epithelial progenitor cells in the murine cornea.

    Science.gov (United States)

    Di Girolamo, N; Bobba, S; Raviraj, V; Delic, N C; Slapetova, I; Nicovich, P R; Halliday, G M; Wakefield, D; Whan, R; Lyons, J G

    2015-01-01

    Stem cell (SC) division, deployment, and differentiation are processes that contribute to corneal epithelial renewal. Until now studying the destiny of these cells in a living mammal has not been possible. However, the advent of inducible multicolor genetic tagging and powerful imaging technologies has rendered this achievable in the translucent and readily accessible murine cornea. K14CreER(T2)-Confetti mice that harbor two copies of the Brainbow 2.1 cassette, yielding up to 10 colors from the stochastic recombination of fluorescent proteins, were used to monitor K-14(+) progenitor cell dynamics within the corneal epithelium in live animals. Multicolored columns of cells emerged from the basal limbal epithelium as they expanded and migrated linearly at a rate of 10.8 µm/day toward the central cornea. Moreover, the permanent expression of fluorophores, passed on from progenitor to progeny, assisted in discriminating individual clones as spectrally distinct streaks containing more than 1,000 cells within the illuminated area. The centripetal clonal expansion is suggestive that a single progenitor cell is responsible for maintaining a narrow corridor of corneal epithelial cells. Our data are in agreement with the limbus as the repository for SC as opposed to SC being distributed throughout the central cornea. This is the first report describing stem/progenitor cell fate determination in the murine cornea using multicolor genetic tracing. This model represents a powerful new resource to monitor SC kinetics and fate choice under homeostatic conditions, and may assist in assessing clonal evolution during corneal development, aging, wound-healing, disease, and following transplantation. © 2014 AlphaMed Press.

  5. Experience of Comamonas Acidovorans Keratitis with Delayed Onset and Treatment Response in Immunocompromised Cornea

    OpenAIRE

    Lee, Sang Mok; Kim, Mee Kum; Lee, Jae Lim; Wee, Won Ryang; Lee, Jin Hak

    2008-01-01

    Purpose To report 2 cases of Comamonas Acidovorans keratitis in immunocompromised cornea. Methods A complete review of the medical records of the two cases of Comamonas acidovorans keratitis. Results We found some similarities in clinical courses of two cases. Both of them showed development of keratitis during the management with corticosteroids, delayed onset, slow response to antibiotics, and relatively less affected corneal epithelium. Conclusions Comamonas Acidovorans is known as a less ...

  6. Atmospheric-Pressure Cold Plasma Induces Transcriptional Changes in Ex Vivo Human Corneas.

    Directory of Open Access Journals (Sweden)

    Umberto Rosani

    Full Text Available Atmospheric pressure cold plasma (APCP might be considered a novel tool for tissue disinfection in medicine since the active chemical species produced by low plasma doses, generated by ionizing helium gas in air, induces reactive oxygen species (ROS that kill microorganisms without substantially affecting human cells.In this study, we evaluated morphological and functional changes in human corneas exposed for 2 minutes (min to APCP and tested if the antioxidant n-acetyl l-cysteine (NAC was able to inhibit or prevent damage and cell death.Immunohistochemistry and western blotting analyses of corneal tissues collected at 6 hours (h post-APCP treatment demonstrated no morphological tissue changes, but a transient increased expression of OGG1 glycosylase that returned to control levels in 24 h. Transcriptome sequencing and quantitative real time PCR performed on different corneas revealed in the treated corneas many differentially expressed genes: namely, 256 and 304 genes showing expression changes greater than ± 2 folds in the absence and presence of NAC, respectively. At 6 h post-treatment, the most over-expressed gene categories suggested an active or enhanced cell functioning, with only a minority of genes specifically concerning oxidative DNA damage and repair showing slight over-expression values (<2 folds. Moreover, time-related expression analysis of eight genes up-regulated in the APCP-treated corneas overall demonstrated the return to control expression levels after 24 h.These findings of transient oxidative stress accompanied by wide-range transcriptome adjustments support the further development of APCP as an ocular disinfectant.

  7. Pathogenic strains of Acanthamoeba are recognized by TLR4 and initiated inflammatory responses in the cornea.

    Directory of Open Access Journals (Sweden)

    Hassan Alizadeh

    Full Text Available Free-living amoebae of the Acanthamoeba species are the causative agent of Acanthamoeba keratitis (AK, a sight-threatening corneal infection that causes severe pain and a characteristic ring-shaped corneal infiltrate. Innate immune responses play an important role in resistance against AK. The aim of this study is to determine if Toll-like receptors (TLRs on corneal epithelial cells are activated by Acanthamoeba, leading to initiation of inflammatory responses in the cornea. Human corneal epithelial (HCE cells constitutively expressed TLR1, TLR2, TLR3, TLR4, and TLR9 mRNA, and A. castellanii upregulated TLR4 transcription. Expression of TLR1, TLR2, TLR3, and TLR9 was unchanged when HCE cells were exposed to A. castellanii. IL-8 mRNA expression was upregulated in HCE cells exposed to A. castellanii. A. castellanii and lipopolysaccharide (LPS induced significant IL-8 production by HCE cells as measured by ELISA. The percentage of total cells positive for TLR4 was higher in A. castellanii stimulated HCE cells compared to unstimulated HCE cells. A. castellanii induced upregulation of IL-8 in TLR4 expressing human embryonic kidney (HEK-293 cells, but not TLR3 expressing HEK-293 cells. TLR4 neutralizing antibody inhibited A. castellanii-induced IL-8 by HCE and HEK-293 cells. Clinical strains but not soil strains of Acanthamoeba activated TLR4 expression in Chinese hamster corneas in vivo and in vitro. Clinical isolates but not soil isolates of Acanthamoeba induced significant (P< 0.05 CXCL2 production in Chinese hamster corneas 3 and 7 days after infection, which coincided with increased inflammatory cells in the corneas. Results suggest that pathogenic species of Acanthamoeba activate TLR4 and induce production of CXCL2 in the Chinese hamster model of AK. TLR4 may be a potential target in the development of novel treatment strategies in Acanthamoeba and other microbial infections that activate TLR4 in corneal cells.

  8. Public Health Implications of the 1540 nm Laser on the Cornea

    Science.gov (United States)

    2007-05-30

    of Public Health Degree 30 May 2007 - Thomas J01vfson, Ph.D. Department of Preventive Medicine & Biometrics Committee Member Christine Kasper, ’,D...Xu and Alfano 2005) This absorption characteristic is useful in refractive surgery of the eye because the cornea is approximately 80% water...retina. Invest Ophthalmol Vis Sci 35: 3032-44; 1994. Xu M, Alfano RR. Fractal mechanisms of light scattering in biological tissue and cells. Opt

  9. Molecular Hydrogen Effectively Heals Alkali-Injured Cornea via Suppression of Oxidative Stress

    Czech Academy of Sciences Publication Activity Database

    Čejka, Čestmír; Kössl, Jan; Heřmánková, Barbora; Holáň, Vladimír; Čejková, Jitka

    2017-01-01

    Roč. 2017, č. 2017 (2017), s. 8906027 ISSN 1942-0900 R&D Projects: GA ČR(CZ) GA14-12580S; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) LO1508; GA MŠk(CZ) LO1309 Institutional support: RVO:68378041 Keywords : 4-coumaric acid * rabbit cornea * nitric-oxide Subject RIV: FF - HEENT, Dentistry OBOR OECD: Ophthalmology Impact factor: 4.593, year: 2016

  10. Dexamethasone Drug Eluting Nanowafers Control Inflammation in Alkali-Burned Corneas Associated With Dry Eye

    Science.gov (United States)

    Bian, Fang; Shin, Crystal S.; Wang, Changjun; Pflugfelder, Stephen C.; Acharya, Ghanashyam; De Paiva, Cintia S.

    2016-01-01

    Purpose To evaluate the efficacy of a controlled release dexamethasone delivery system for suppressing inflammation in an ocular burn + desiccating stress (OB+DS) model. Methods Nanowafers (NW) loaded with Dexamethasone (Dex, 10 μg) or vehicles (2.5% Methylcellulose; MC) were fabricated using hydrogel template strategy. C57BL/6 mice were subjected to unilateral alkali ocular burn with concomitant desiccating stress for 2 or 5 days and topically treated either with 2 μL of 0.1% Dex or vehicle four times per day and compared with mice that had MC-NW or Dex-NW placed on their corneas. Clinical parameters were evaluated daily. Mice were euthanized after 2 or 5 days. Quantitative PCR evaluated the expression of inflammatory cytokines IL-1β and IL-6 and matrix metalloproteinases (MMP) in whole cornea lysates. Myeloperoxidase activity (MPO) was measured using a commercial kit in cornea lysates. Results Both Dex drop and Dex-NW groups had significantly lower corneal opacity scores compared with their vehicles. Both Dex drops and Dex-NW significantly decreased expression of IL-1β, IL-6, and MMP-9 RNA transcripts compared with vehicle drops or wafers 2 and 5 days after the initial lesion. A significant lower number of neutrophils was found in both Dex treatment groups and this was accompanied by decreased MPO activity compared with vehicle controls. Conclusions Dex-NW has efficacy equal to Dex drops in preserving corneal clarity and decreasing expression of MMPs and inflammatory cytokines of the corneas of mice subjected to an OB+DS model. PMID:27327581

  11. In vivo 3D measurement of moxifloxacin and gatifloxacin distributions in the mouse cornea using multiphoton microscopy

    OpenAIRE

    Lee, Seunghun; Lee, Jun Ho; Park, Jin Hyoung; Yoon, Yeoreum; Chung, Wan Kyun; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2016-01-01

    Moxifloxacin and gatifloxacin are fourth-generation fluoroquinolone antibiotics used in the clinic to prevent or treat ocular infections. Their pharmacokinetics in the cornea is usually measured from extracted ocular fluids or tissues, and in vivo direct measurement is difficult. In this study multiphoton microscopy (MPM), which is a 3D optical microscopic technique based on multiphoton fluorescence, was applied to the measurement of moxifloxacin and gatifloxacin distribution in the cornea. I...

  12. Study of the protective properties of paraaminobenzoic acid for cornea of adult rats under X-radiation

    International Nuclear Information System (INIS)

    Stroeva, O.G.; Panova, I.G.; Mel'nikova, I.I.

    1997-01-01

    To test the efficiency of para-aminobenzoic acid (PABA) as a radioprotector for mammal tissues the protective properties of PABA for cornea of adult rats-males exposed to single whole-body irradiation were studied. X-irradiation was performed using RUM-17 facility at the dose of 5 Gy (dose rate is of 0.886 Gy/min). Results obtained prove reliably radioprotective and therapeutic effect of PABA on the cornea cells [ru

  13. Autologous conjunctiva transplantation with stem cells on edge of cornea for recurrent pterygium

    Directory of Open Access Journals (Sweden)

    Yun Wang

    2013-10-01

    Full Text Available AIM: To observe the clinical effectiveness and practicality the autologous conjunctiva transplantation with stem cells on edge of cornea for recurrent pterygium.METHODS: Of the 53 recurrent pterygium patients(57 eyes, after all pathological tissues were removed, underwent the autologous conjunctiva transplantation with stem cells on edge of cornea which were locked above conjunctival transplantation of the operated eye.RESULTS: Postopretive follow-up was 1-12 months for all 57 eyes, of which 3 eyes(5%relapsed. The corneoscleral autolysis was occurred in one eye and surgery treatment was conducted. Corneal wounds were healing and transplantations survived well for the remaining 53 patients without obvious surgical marks. Cure rate was 93%.CONCLUSION: Autologous conjunctiva transplantation with stem cells on edge of cornea for recurrent pterygium can meet the aesthetic requirements of the some patients, with the advantages of obtaining material easily, faster wound healing, lower postoperative recurrence rate, meeting the aesthetic needs of some patients and improving postoperative results. Thus, it is an ideal surgery and is worthy of applying on primary hospital.

  14. The Effect of Systemic Amantadine Sulfate on Malondialdehyde and Total Thiol Levels in Rat Corneas

    Directory of Open Access Journals (Sweden)

    Züleyha Yalniz-Akkaya

    2014-01-01

    Full Text Available Purpose: To evaluate the malondialdehyde (MDA and total thiol (sulfhydryl, SH levels in rat corneas after intraperitoneal injection of amantadine sulfate. Methods: A total of 12 Wistar albino rats were divided into two groups: control group (n = 6 and amantadine group (n = 6. Balanced salt solution (1 mL, 0.9% NaCl, twice/day was injected into rats in control group. Amantadine sulfate (2 mg/1 mL, twice/day was injected into rats in amantadine group. In each group, two rats were injected for 1 week, two received injections for 1 month, and two rats received injections for 3 months. The corneas were homogenized and MDA and SH levels were measured spectroflourometrically. Results: In control group, median MDA and SH levels were 2.37 (range, 0.92-3.60 and 25.35 (range, 6.30-54.0 nmol/mg, respectively. In amantadine group, median MDA and SH levels were 3.57 (range, 1.25-5.92 and 32.65 (range, 3.30-48.3 nmol/mg, respectively. The difference between this two groups regarding MDA (P = 0.14 and SH (P = 1.0 levels was statistically insignificant. Conclusion: Systemically administered amantadine sulfate seems not to cause MDA and SH imbalance in rat corneas.

  15. Measurement and modeling of diffusion kinetics of a lipophilic molecule across rabbit cornea.

    Science.gov (United States)

    Gupta, Chhavi; Chauhan, Anuj; Mutharasan, Raj; Srinivas, Sangly P

    2010-04-01

    To develop a kinetic model for representing the diffusion and partitioning of Rhodamine B (RhB), a fluorescent lipophilic molecule, across the cornea for gaining insights into pharmacokinetics of topical drugs to the eye. Rabbit corneas mounted underneath a custom-built scanning microfluorometer were perfused with Ringers on both sides of the tissue. After a step change in RhB on the tear side, transients of trans-corneal fluorescence of RhB were measured at a depth resolution approximately 8 microm. RhB distribution exhibited discontinuities at the interface between epithelium and stroma, and between stroma and endothelium. In each of the layers, fluorescence was non-uniform. Fluorescence was elevated in the epithelium and endothelium relative to the stroma. Modeling of RhB transport by diffusion in each layer and stipulation of partitioning of RhB at the cellular interfaces were required to account for trans-corneal penetration kinetics of RhB. The model parameters, estimated using the unsteady state trans-corneal RhB profiles, were found to be sensitive, and the model predicted the experimental profiles accurately. Conventional pharmacokinetic models that depict cornea as a single compartment do not predict the depth-dependent kinetics of RhB penetration. The proposed model incorporates realistic transport mechanisms and thereby highlights the influence of physicochemical properties of drugs on trans-corneal kinetics.

  16. Adjunctive cryotherapy for pigmentary keratitis in dogs: a study of 16 corneas.

    Science.gov (United States)

    Azoulay, Thierry

    2014-07-01

    To assess whether soft cryotherapy (dimethylether, isobutene, and propane) can remove pigmentation of the cornea that has accumulated under different conditions when conventional therapy has been unsuccessful. Nine dogs with unilateral or bilateral corneal pigmentation (16 eyes) were included based on progressive corneal pigmentation that was unresponsive to long-term etiological treatment. The dogs had keratoconjunctivitis sicca or chronic superficial keratitis. A cryogen of 95% dimethylether, 3% isobutane, and 2% propane was applied to the pigmented areas of each cornea under anesthesia. Initial corneal pigmentation and changes were documented over the entire study period using a grading scheme and clinical photographs. Most of the pigment deposits were gone by 5-15 days after cryosurgery. Postoperatively, the dogs showed some corneal edema and corneo-conjunctival inflammation, and three dogs had superficial corneal ulcers; these symptoms had resolved by 1 month after the procedure. Follow-up for more than 90 days was available in five dogs (nine corneas), and we observed total or partial repigmentation when the underlying disease was not controlled. A new cryotherapy procedure was successfully performed in two of these dogs. Given the sensitivity to cold of melanocytes, cryotherapy is a viable adjunctive treatment for refractory severe corneal pigmentation. Etiological treatment remains necessary to prevent pigmentation from rapidly reappearing. Only a few dogs were followed for more than 90 days; further study is necessary to evaluate the long-term safety and efficacy of soft cryotherapy. © 2013 American College of Veterinary Ophthalmologists.

  17. Femtosecond laser cutting of human corneas for the subbasal nerve plexus evaluation.

    Science.gov (United States)

    Kowtharapu, B S; Marfurt, C; Hovakimyan, M; Will, F; Richter, H; Wree, A; Stachs, O; Guthoff, R F

    2017-01-01

    Assessment of various morphological parameters of the corneal subbasal nerve plexus is a valuable method of documenting the structural and presumably functional integrity of the corneal innervation in health and disease. The aim of this work is to establish a rapid, reliable and reproducible method for visualization of the human corneal SBP using femtosecond laser cut corneal tissue sections. Trephined healthy corneal buttons were fixed and processed using TissueSurgeon-a femtosecond laser based microtome, to obtain thick tissue sections of the corneal epithelium and anterior stroma cut parallel to the ocular surface within approximately 15 min. A near infrared femtosecond laser was focused on to the cornea approximately 70-90 μm from the anterior surface to induce material separation using TissueSurgeon. The obtained corneal sections were stained following standard immunohistochemical procedures with anti-neuronal β-III tubulin antibody for visualization of the corneal nerves. Sections that contained the epithelium and approximately 20-30 μm of anterior stroma yielded excellent visualisation of the SBP with minimal optical interference from underlying stromal nerves. In conclusion, the results of this study have demonstrated that femtosecond laser cutting of the human cornea offers greater speed, ease and reliability than standard tissue preparation methods for obtaining high quality thick sections of the anterior cornea cut parallel to the ocular surface. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

  18. Desiccating Stress-Induced MMP Production and Activity Worsens Wound Healing in Alkali-Burned Corneas

    Science.gov (United States)

    Bian, Fang; Pelegrino, Flavia S. A.; Pflugfelder, Stephen C.; Volpe, Eugene A.; Li, De-Quan; de Paiva, Cintia S.

    2015-01-01

    Purpose To evaluate the effects of dry eye on ocular surface protease activity and sight threatening corneal complications following ocular surface chemical injury. Methods C57BL/6 mice were subjected to unilateral alkali burn (AB) with or without concomitant dry eye for 2 or 5 days. Mice were observed daily for appearance of corneal perforation. Whole corneas were harvested and lysed for RNA extraction. Quantitative real-time PCR was performed to measure expression of inflammation cytokines, matrix metalloproteinases (MMP). Matrix metalloproteinase–9 activity, gelatinase activity, and myeloperoxidase (MPO) activity were evaluated in corneal lysates. Presence of infiltrating neutrophils was evaluated by immunohistochemistry and flow cytometry. Results Eyes subjected to the combined model of AB and dry eye (CM) had 20% sterile corneal perforation rate as soon as 1 day after the initial injury, which increased to 35% by 5 days, delayed wound closure and increased corneal opacity. Increased levels of IL-1β, -6, and MMPs-1, -3, -8, -9, and -13, and chemokine (C-X-C motif) ligand 1 (CSCL1) transcripts were found after 2 days in CM compared with AB corneas. Increased MMP-1, -3, -9, and -13 immunoreactivity and gelatinolytic activity were seen in CM corneas compared with AB. Increased neutrophil infiltration and MPO activity was noted in the CM group compared with AB 2 days post injury. Conclusions Desiccating stress worsens outcome of ocular AB, creating a cytokine and protease storm with greater neutrophil infiltration, increasing the risk of corneal perforation. PMID:26225631

  19. The LOCUS interface to the MFE database

    International Nuclear Information System (INIS)

    Miner, W.H. Jr.

    1991-01-01

    The MFE database now consists of over 900 shots from TFTR, PDX, PLT, T-10, JT-60, TEXT, JET and ASDEX. A variety of discharge conditions is represented, ranging from single time slice Ohmic discharges to multiple time-slice auxiliary heated discharges. Included with most datasets is a reference that describes the experiment being performed when the data was taken. The MFE database is currently implemented under INGRES on a VAX that is on Internet. LOCUS, a database utility, developed at the Princeton Plasma Physics Laboratory is now available as an interface to the database. The LOCUS front end provides a graphic interface to the database from any generic graphics terminal that supports Tektronix 4010 emulation. It provides a variety of procedures for extracting, manipulating and graphing data from the MFE database. In order to demonstrate the capabilities of the LOCUS interface, the authors examine, in detail, one of the recently added JET, H-mode discharges. In this example, they address some new concepts such as monitor functions, which have been introduced in order to help users more fully understand the multiple time-slice datasets. They also describe some of the more advanced techniques available in LOCUS for data access and manipulation. Specific areas of interest that are discussed are searching for and retrieving datasets, graphics, data fitting, and linear regression analysis

  20. Property-based design: optimization and characterization of polyvinyl alcohol (PVA) hydrogel and PVA-matrix composite for artificial cornea.

    Science.gov (United States)

    Jiang, Hong; Zuo, Yi; Zhang, Li; Li, Jidong; Zhang, Aiming; Li, Yubao; Yang, Xiaochao

    2014-03-01

    Each approach for artificial cornea design is toward the same goal: to develop a material that best mimics the important properties of natural cornea. Accordingly, the selection and optimization of corneal substitute should be based on their physicochemical properties. In this study, three types of polyvinyl alcohol (PVA) hydrogels with different polymerization degree (PVA1799, PVA2499 and PVA2699) were prepared by freeze-thawing techniques. After characterization in terms of transparency, water content, water contact angle, mechanical property, root-mean-square roughness and protein adsorption behavior, the optimized PVA2499 hydrogel with similar properties of natural cornea was selected as a matrix material for artificial cornea. Based on this, a biomimetic artificial cornea was fabricated with core-and-skirt structure: a transparent PVA hydrogel core, surrounding by a ringed PVA-matrix composite skirt that composed of graphite, Fe-doped nano hydroxyapatite (n-Fe-HA) and PVA hydrogel. Different ratio of graphite/n-Fe-HA can tune the skirt color from dark brown to light brown, which well simulates the iris color of Oriental eyes. Moreover, morphologic and mechanical examination showed that an integrated core-and-skirt artificial cornea was formed from an interpenetrating polymer network, no phase separation appeared on the interface between the core and the skirt.

  1. Evaluation of the adhesive properties of the cornea by means of optical coherence tomography in patients with meibomian gland dysfunction and lacrimal tear deficiency.

    Science.gov (United States)

    Napoli, Pietro Emanuele; Coronella, Franco; Satta, Giovanni Maria; Galantuomo, Maria Silvana; Fossarello, Maurizio

    2014-01-01

    The aim was to determine the influence of meibomian gland dysfunction (MGD) and aqueous tear deficiency dry eye (ADDE) on the adhesive properties of the central cornea by means of optical coherence tomography (OCT), and to investigate the relationship between corneal adhesiveness and classical tear tests, as well as the reliability of results, in these lacrimal functional unit disorders. Prospective, case-control study. Twenty-eight patients with MGD and 27 patients with ADDE were studied. A group of 32 healthy subjects of similar age and gender distribution served as a control group. The adhesive properties of the anterior corneal surface were measured by OCT, based on the retention time of adhesion marker above it, in all participants. An excellent (≥5 minutes), borderline (within 3-5 minutes), fair (within 1-3 minutes) and poor (<1 minute) values of corneal adhesiveness were found, respectively, in 0%, 7.1%, 64.3% and 28.6% of MGD, in 0%, 7.4%, 63% and 29.6% of ADDE, and in 31.3%, 65.6%, 3.1% and 0% of healthy patients. The differences in time of corneal adhesiveness between MGD and healthy patients, as well as between ADDE and healthy patients, were found to be statistically significant (p<0.001; p<0.001; respectively). Conversely, no statistical significant differences between MGD and ADDE were found (p = 0.952). Data analysis revealed a statistically significant correlation between corneal adhesiveness and clinical tests of dry eye, as well as an excellent degree of inter-rater reliability and reproducibility for OCT measurements (p<0.001). ADDE and MGD share similar abnormalities on OCT imaging. Decreased adhesive properties of the anterior cornea were identified as a common feature of MGD and ADDE. This simple OCT approach may provide new clues into the mechanism and evaluation of dry eye syndrome.

  2. Evaluation of the adhesive properties of the cornea by means of optical coherence tomography in patients with meibomian gland dysfunction and lacrimal tear deficiency.

    Directory of Open Access Journals (Sweden)

    Pietro Emanuele Napoli

    Full Text Available The aim was to determine the influence of meibomian gland dysfunction (MGD and aqueous tear deficiency dry eye (ADDE on the adhesive properties of the central cornea by means of optical coherence tomography (OCT, and to investigate the relationship between corneal adhesiveness and classical tear tests, as well as the reliability of results, in these lacrimal functional unit disorders.Prospective, case-control study.Twenty-eight patients with MGD and 27 patients with ADDE were studied. A group of 32 healthy subjects of similar age and gender distribution served as a control group. The adhesive properties of the anterior corneal surface were measured by OCT, based on the retention time of adhesion marker above it, in all participants.An excellent (≥5 minutes, borderline (within 3-5 minutes, fair (within 1-3 minutes and poor (<1 minute values of corneal adhesiveness were found, respectively, in 0%, 7.1%, 64.3% and 28.6% of MGD, in 0%, 7.4%, 63% and 29.6% of ADDE, and in 31.3%, 65.6%, 3.1% and 0% of healthy patients. The differences in time of corneal adhesiveness between MGD and healthy patients, as well as between ADDE and healthy patients, were found to be statistically significant (p<0.001; p<0.001; respectively. Conversely, no statistical significant differences between MGD and ADDE were found (p = 0.952. Data analysis revealed a statistically significant correlation between corneal adhesiveness and clinical tests of dry eye, as well as an excellent degree of inter-rater reliability and reproducibility for OCT measurements (p<0.001.ADDE and MGD share similar abnormalities on OCT imaging. Decreased adhesive properties of the anterior cornea were identified as a common feature of MGD and ADDE. This simple OCT approach may provide new clues into the mechanism and evaluation of dry eye syndrome.

  3. The effect of single and repeated UVB radiation on rabbit cornea.

    Science.gov (United States)

    Fris, Miroslav; Tessem, May-Britt; Cejková, Jitka; Midelfart, Anna

    2006-12-01

    Cumulative effect of ultraviolet radiation (UVR) is an important aspect of UV corneal damage. The purpose of this study was to apply high resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS 1H NMR) spectroscopy to evaluate the effect of single and repeated UV radiation exposure of the same overall dose on the rabbit cornea. Corneal surfaces of 24 normal rabbit eyes were examined for the effects of UVB exposure (312 nm). In the first group (UVB1), animals were irradiated with a single dose (3.12 J/cm2; 21 min) of UVB radiation. The animals in the second group (UVB2) were irradiated three times for 7 min every other day (dose of 1.04 J/cm2; days 1, 3, 5) to give the same overall dose (3.12 J/cm2). The third group served as an untreated control group. One day after the last irradiation, the animals were sacrificed, and the corneas were removed and frozen. HR-MAS 1H NMR spectra from intact corneas were obtained. Special grouping patterns among the tissue samples and the relative percentage changes in particular metabolite concentrations were evaluated using modern statistical methods (multivariate analysis, one-way ANOVA). The metabolic profile of both groups of UVB-irradiated samples was significantly different from the control corneas. Substantial decreases in taurine, hypo-taurine and choline-derivatives concentrations and substantial elevation in glucose and betaine levels were observed following the UVR exposure. There was no significant difference between the effect of a single and repeated UVB irradiation of the same overall dose. For the first time, the effects of single and repeated UVR doses on the metabolic profile of the rabbit cornea were analysed and compared. The combination of HR-MAS 1H NMR spectroscopy and modern statistical methods (multivariate analysis, one-way ANOVA) proved suitable to assess the overall view of the metabolic alterations in the rabbit corneal tissue following UVB radiation exposure.

  4. The Impact of Locus of Control on Language Achievement

    Science.gov (United States)

    Nodoushan, Mohammad Ali Salmani

    2012-01-01

    This study hypothesized that students' loci of control affected their language achievement. 198 (N = 198) EFL students took the Rotter's (1966) locus of control test and were classified as locus-internal (ni = 78), and locus-external (ne = 120). They then took their ordinary courses and at the end of the semester, they were given their exams.…

  5. Self-Esteem, Locus of Control, and Student Achievement.

    Science.gov (United States)

    Sterbin, Allan; Rakow, Ernest

    The direct effects of locus of control and self-esteem on standardized test scores were studied. The relationships among the standardized test scores and measures of locus of control and self-esteem for 12,260 students from the National Education Longitudinal Study 1994 database were examined, using the same definition of locus of control and…

  6. Locus of control fails to mediate between stress and anxiety and depression in parents of children with a developmental disorder.

    Science.gov (United States)

    Hamlyn-Wright, Sarah; Draghi-Lorenz, Riccardo; Ellis, Jason

    2007-11-01

    Stress, anxiety and depression are raised amongst parents of children with a developmental disorder. However, the processes by which stress leads to depression and anxiety are poorly understood. In a cross-sectional survey, levels of parental stress, depression and anxiety were compared between parents of children with an autistic disorder, children with Down's syndrome and children with no disorder (N = 619) and the mediational role of locus of control was examined. Anxiety and depression were higher in parents of children with a disorder, and highest in parents of children with autism. Locus of control was more external in parents of children with autism. Locus of control failed to mediate the relationship between stress and both anxiety and depression in parents of children with a disorder. This suggests that help for parents of a child with a disorder may be effective if focused on the sources of stress rather than perceived control over events.

  7. Pleiotropic roles of Clostridium difficile sin locus

    Science.gov (United States)

    Ou, Junjun; Dupuy, Bruno

    2018-01-01

    Clostridium difficile is the primary cause of nosocomial diarrhea and pseudomembranous colitis. It produces dormant spores, which serve as an infectious vehicle responsible for transmission of the disease and persistence of the organism in the environment. In Bacillus subtilis, the sin locus coding SinR (113 aa) and SinI (57 aa) is responsible for sporulation inhibition. In B. subtilis, SinR mainly acts as a repressor of its target genes to control sporulation, biofilm formation, and autolysis. SinI is an inhibitor of SinR, so their interaction determines whether SinR can inhibit its target gene expression. The C. difficile genome carries two sinR homologs in the operon that we named sinR and sinR’, coding for SinR (112 aa) and SinR’ (105 aa), respectively. In this study, we constructed and characterized sin locus mutants in two different C. difficile strains R20291 and JIR8094, to decipher the locus’s role in C. difficile physiology. Transcriptome analysis of the sinRR’ mutants revealed their pleiotropic roles in controlling several pathways including sporulation, toxin production, and motility in C. difficile. Through various genetic and biochemical experiments, we have shown that SinR can regulate transcription of key regulators in these pathways, which includes sigD, spo0A, and codY. We have found that SinR’ acts as an antagonist to SinR by blocking its repressor activity. Using a hamster model, we have also demonstrated that the sin locus is needed for successful C. difficile infection. This study reveals the sin locus as a central link that connects the gene regulatory networks of sporulation, toxin production, and motility; three key pathways that are important for C. difficile pathogenesis. PMID:29529083

  8. The algebraic locus of Feynman integrals

    OpenAIRE

    Kol, Barak

    2016-01-01

    In the Symmetries of Feynman Integrals (SFI) approach, a diagram's parameter space is foliated by orbits of a Lie group associated with the diagram. SFI is related to the important methods of Integrations By Parts and of Differential Equations. It is shown that sometimes there exist a locus in parameter space where the set of SFI differential equations degenerates into an algebraic equation, thereby enabling a solution in terms of integrals associated with degenerations of the diagram. This i...

  9. Bipolar disorder: Evidence for a major locus

    Energy Technology Data Exchange (ETDEWEB)

    Spence, M.A.; Flodman, P.L. [Univ. of California, Irvine, CA (United States); Sadovnick, A.D.; Ameli, H. [Univ. of British Columbia, Vancouver (Canada)] [and others

    1995-10-09

    Complex segregation analyses were conducted on families of bipolar I and bipolar II probands to delineate the mode of inheritance. The probands were ascertained from consecutive referrals to the Mood Disorder Service, University Hospital, University of British Columbia and diagnosed by DSM-III-R and Research Diagnostic Criteria. Data were available on over 1,500 first-degree relatives of the 186 Caucasian probands. The purpose of the analyses was to determine if, after correcting for age and birth cohort, there was evidence for a single major locus. Five models were fit to the data using the statistical package SAGE: (1) dominant, (2) recessive, (3) arbitrary mendelian inheritance, (4) environmental, and (5) no major effects. A single dominant, mendelian major locus was the best fitting of these models for the sample of bipolar I and II probands when only bipolar relatives were defined as affected (polygenic inheritance could not be tested). Adding recurrent major depression to the diagnosis {open_quotes}affected{close_quotes} for relatives reduced the evidence for a major locus effect. Our findings support the undertaking of linkage studies and are consistent with the analyses of the National Institutes of Mental Health (NIMH) Collaborative Study data by Rice et al. and Blangero and Elston. 39 refs., 4 tabs.

  10. Genetic Linkage Analysis of DFNB2 Locus with Autosomal Recessive Hearing Loss in Families Negative for GJB2 Mutations in Khuzestan Province

    Directory of Open Access Journals (Sweden)

    Parisa Tahmasebi

    2016-09-01

    Full Text Available Abstract Background: Hearing loss is a common sensory impairment in humans which half of its causes are genetic reasons. Genetic hearing loss can be divided into the two types of syndromic and non-syndromic, which 80% of non-syndromic cases is Autosomal Recessive Non-Syndromic Hearing Loss. The aim of the present research is to determine the contribution of DFNB2 locus (MYO7A gene in causing an autosomal recessive hearing loss in the one group of the deaf families of Khuzestan province. Materials and Methods: This study was conducted on 26 families with autosomal recessive hearing loss (with 4 patients and negative for GJB2 mutations in Khuzestan province. 22 families suffered from ARNSHL and 4 families suffered from Usher syndrome. Linkage analysis was performed by using STR (Short Tandem Repeat markers related to DFNB2 locus. Each family’s genotype was determined by PCR-PAGE method. Furthermore, haplotypes drawing and LOD score calculations were performed. Results: From 26 families with hearing loss participating in this research, following genetic linkage analysis and haplotypes drawing, two families (7.7% of the families showed linkage to DFNB2 locus. One family (4.5% suffered from ARNSHL and another family suffered from Usher syndrome. Conclusion: The results of the present research show that the contribution of DFNB2 locus in causing hearing loss in the population of Khuzestan province was similar to other studies conducted in Iran and this locus with other important loci should be considered to check in the hearing loss panel.

  11. Proteomic Analyses of the Acute Tissue Response for Explant Rabbit Corneas and Engineered Corneal Tissue Models Following In Vitro Exposure to 1540 nm Laser Light

    National Research Council Canada - National Science Library

    Eurell, T. E; Johnson, T. E; Roach, W. P

    2005-01-01

    Two-dimensional electrophoresis and histomorphometry were used to determine if equivalent protein changes occurred within native rabbit corneas and engineered corneal tissue models following in vitro...

  12. Expression of multidrug resistance associated protein 5 (MRP5) on cornea and its role in drug efflux.

    Science.gov (United States)

    Karla, Pradeep K; Quinn, Tim L; Herndon, Betty L; Thomas, Priscilla; Pal, Dhananjay; Mitra, Ashim

    2009-04-01

    The purpose of this manuscript is to investigate the presence of nucleoside/nucleotide efflux transporter in cornea and to evaluate the role in ocular drug efflux. RT-PCR, immunoprecipitation followed by Western blot analysis and immunostaining were employed to establish molecular presence of multidrug resistance associated protein 5 (MRP5) on cornea. Corneal efflux by MRP5 was studied with bis(POM)-PMEA and acyclovir using rabbit and human corneal epithelial cells along with MRP5 over expressing cells (MDCKII-MRP5). Ex vivo studies using excised rabbit cornea and in vivo ocular microdialysis in male New Zealand white rabbits were used to further evaluate the role of MRP5 in conferring ocular drug resistance. RT-PCR confirms the expression of MRP5 in both rabbit and human corneal epithelial cells along with MDCKII-MRP5 cells. Immunoprecipitation followed by Western blot analysis using a rat (M511-54) monoclonal antibody that reacts with human epitope confirms the expression of MRP5 protein in human corneal epithelial cells and MDCKII-MRP5 cells. Immunostaining performed on human cornea indicates the localization of this efflux pump on both epithelium and endothelium. Efflux studies reveal that depletion of ATP decreased PMEA efflux significantly. MRP5 inhibitors also diminished PMEA and acyclovir efflux. However, depletion of glutathione did not alter efflux. MDR1 and MRP2 did not contribute to PMEA efflux. However, MRP2 is involved in acyclovir efflux while MDR1 do not participate in this process. TLC/autoradiography suggested the conversion of bis(POM)-PMEA to PMEA in rabbit and human corneal epithelial cells. Two well known antiglaucoma drugs, bimatoprost and latanoprost were rapidly effluxed by MRP5. Ex vivo study on intact rabbit corneas demonstrated accumulation of PMEA in cornea in the presence of ATP-depleting medium. In vivo ocular pharmacokinetics also revealed a significant increase in maximum aqueous humor concentration (C(max)) and area under the

  13. Corneal Collagen Cross-Linking with Hypoosmolar Riboflavin Solution in Keratoconic Corneas

    Directory of Open Access Journals (Sweden)

    Shaofeng Gu

    2014-01-01

    Full Text Available Purpose. To report the 12-month outcomes of corneal collagen cross-linking (CXL with a hypoosmolar riboflavin and ultraviolet-A (UVA irradiation in thin corneas. Methods. Eight eyes underwent CXL using a hypoosmolar riboflavin solution after epithelial removal. The corrected distance visual acuity (CDVA, manifest refraction, the mean thinnest corneal thickness (MTCT, and the endothelial cell density (ECD were evaluated before and 6 and 12 months after CXL. Results. The MTCT was 413.9 ± 12.4 μm before treatment and reduced to 381.1 ± 7.3 μm after the removal of the epithelium. After CXL, the thickness decreased to 410.3 ± 14.5 μm at the last follow-up. Before treatment, the mean K-value of the apex of the keratoconus corneas was 58.7 ± 3.5 diopters and slightly decreased (57.7 ± 4.9 diopters at 12 months. The mean CDVA was 0.54 ± 0.23 logarithm of the minimal angle of resolution before treatment and increased to 0.51 ± 0.21 logarithm at the last follow-up. The ECD was 2731.4 ± 191.8 cells/mm2 before treatment and was 2733.4 ± 222.6 cells/mm2 at 12 months after treatment. Conclusions. CXL with a hypoosmolar riboflavin in thin corneas seems to be a promising method for keratoconic eyes with the mean thinnest corneal thickness less than 400 μm without epithelium.

  14. Serotonin syndrome

    Science.gov (United States)

    Hyperserotonemia; Serotonergic syndrome; Serotonin toxicity; SSRI - serotonin syndrome; MAO - serotonin syndrome ... brain area. For example, you can develop this syndrome if you take migraine medicines called triptans together ...

  15. [Results of an internet-based survey amongst members of the German Ophthalmological Society concerning postmortem cornea donation].

    Science.gov (United States)

    Uhlig, C E; Promesberger, J; Hirschfeld, G; Koch, R; Reinhard, T; Seitz, B

    2012-12-01

    Analysis of willingness for postmortem cornea donation by professionals in ophthalmology and their motives in favor of or against donation. 3887 members of the German Ophthalmological Society received an anonymous questionnaire concerning sociodemographic background, physical health, experiences with organ explantation and their former engagement and motives concerning organ and cornea donation. 722 of the questionnaires were partially and 533 completely answered with an average willingness for cornea donation of 79.4%. Significant parameters for cornea donation were gender, former experience with organ explantation, ophthalmological health and fear of false diagnosis of brain death, worse medical treatment or organ commercialization. Of the participants 53.9% suggested the internet as a favorite source of information in this matter. The factors which had a significant impact on cornea donation in this survey seem to be mainly a result of insufficient information. Detailed information regarding this topic should preferentially be presented on internet pages of professional societies and could probably increase donation approval of DOG members.

  16. In vivo 3D measurement of moxifloxacin and gatifloxacin distributions in the mouse cornea using multiphoton microscopy

    Science.gov (United States)

    Lee, Seunghun; Lee, Jun Ho; Park, Jin Hyoung; Yoon, Yeoreum; Chung, Wan Kyun; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2016-05-01

    Moxifloxacin and gatifloxacin are fourth-generation fluoroquinolone antibiotics used in the clinic to prevent or treat ocular infections. Their pharmacokinetics in the cornea is usually measured from extracted ocular fluids or tissues, and in vivo direct measurement is difficult. In this study multiphoton microscopy (MPM), which is a 3D optical microscopic technique based on multiphoton fluorescence, was applied to the measurement of moxifloxacin and gatifloxacin distribution in the cornea. Intrinsic multiphoton fluorescence properties of moxifloxacin and gatifloxacin were characterized, and their distributions in mouse cornea in vivo were measured by 3D MPM imaging. Both moxifloxacin and gatifloxacin had similar multiphoton spectra, while moxifloxacin had stronger fluorescence than gatifloxacin. MPM imaging of mouse cornea in vivo showed (1) moxifloxacin had good penetration through the superficial corneal epithelium, while gatifloxacin had relatively poor penetration, (2) both ophthalmic solutions had high intracellular distribution. In vivo MPM results were consistent with previous studies. This study demonstrates the feasibility of MPM as a method for in vivo direct measurement of moxifloxacin and gatifloxacin in the cornea.

  17. Effects of acetylcholine (ACh) and norepinephrine (NE) on phosphatidylinositol 4,5-bisphosphate (PIP2) turnover in rabbit cornea

    International Nuclear Information System (INIS)

    Akhtar, R.A.; Abdel-Latif, A.A.

    1986-01-01

    Muscarinic cholinergic and α 1 -adrenergic agonists provoke hydrolysis of PIP 2 into diacylglycerol (DG) and inositol trisphosphate (IP 3 ) in a wide variety of tissue. Recently, IP 3 has been shown to mobilize Ca 2+ from ER in several permeabilized tissue preparations. Although rabbit cornea is enriched in ACh and NE, the physiological function of these neurotransmitters is unclear. The present studies were initiated to determine the effects of cholinergic and adrenergic agonists on PIP 2 turnover in the cornea. Addition of ACh or NE (50 μM each) to the 32 P-labeled corneas for 10 min decreased the radioactivity in PIP 2 by 33 and 36%, and increased the radioactivity in phosphatidic acid by 72 and 52%, respectively. When the corneas were labeled with myo-[ 3 H]inositol, ACh and NE increased the accumulation of IP 3 by 92 and 48%, respectively. The effects of ACh and NE on phospholipid labeling and IP 3 accumulation were specifically inhibited by atropine (10 μM) and prazosin (10 μM), respectively. The data suggest the presence of muscarinic cholinergic and α 1 -adrenergic receptors in the rabbit cornea. Furthermore, activation of these receptors leads to cleavage of PIP 2 into DG and IP 3 which may function as second messengers in this tissue

  18. Embryonic chicken cornea and cartilage synthesize type IX collagen molecules with different amino-terminal domains.

    OpenAIRE

    Svoboda, K K; Nishimura, I; Sugrue, S P; Ninomiya, Y; Olsen, B R

    1988-01-01

    We have analyzed embryonic chicken cornea for the presence of type IX collagen mRNA and protein. Using RNA transfer blot analysis, we demonstrate that alpha 1(IX) and alpha 2(IX) mRNAs are expressed by corneal epithelial cells at the time that the primary stromal components are synthesized. The levels of the mRNAs decrease with increasing developmental age and are barely detectable at day 11 of development. In contrast, type IX collagen protein is detectable by immunofluorescence at days 5 an...

  19. Proliferative activity of endotheliocytes of growing capillaries of the rabbit cornea

    International Nuclear Information System (INIS)

    Gurina, O.Yu.; Mamontov, S.G.; Banin, V.V.

    1987-01-01

    The authors studied the intensity of DNA synthesis by cells of newly formed capillaries, growing in the rabbit cornea, after infliction of a silver nitrate burn and local application of colchicine. The intensity of capillary growth was investigated during stimulation and a combination of the burn with colchicine. Changes in activity of DNA synthesis by the endotheliocytes of newly formed capillaries during exposure throughout growth were also investigated. The intensity of cell proliferation was studied by measuring the incorporation of tritium-labelled thymidine into the endotheoiocyte nuclei

  20. Comparison of Scheimpflug imaging parameters between steep and keratoconic corneas of Caucasian eyes

    Directory of Open Access Journals (Sweden)

    Huseynova T

    2016-04-01

    Full Text Available Tukezban Huseynova,1 Farah Abdulaliyeva,2 Michele Lanza3 1Briz-L Eye Clinic, 2National Ophthalmology Center, Baku, Azerbaijan; 3Second University of Naples, Caserta, Campania, Italy Purpose: To compare the keratometric and pachymetric parameters of healthy eyes with those affected by steep cornea and keratoconus (KC using Scheimpflug camera.Setting: Briz-L Eye Clinic, Baku, Azerbaijan.Design: A cross-sectional study.Methods: In this study, 49 KC (Amsler–Krumeich stage 1 eyes and 36 healthy eyes were enrolled. A complete ophthalmic evaluation and a Scheimpflug camera scan were performed in every eye included in the study. Tomographic parameters such as parameters from the front and back cornea, maximum keratometry reading (Kmax, corneal volume (CV, anterior chamber volume (ChV, anterior chamber depth (ACD, anterior chamber angle (AC angle, keratometric power deviation (KPD, maximum front elevation (Max FE, and maximum back elevation (Max BE, as well as pachymetric progression indices (PPI, Ambrosio relational thickness (ART, index of surface variance (ISV, index of vertical asymmetry (IVA, center keratoconus index (CKI, index of height asymmetry (IHA, index of height decentration (IHD, and radius minimum (RM were collected and statistically compared between the two groups.Results: PPI, ART, ISV, IVA, CKI, IHA, IHD, and RM parameter values were significantly different (P<0.05 between the KC and healthy eyes. There were no significant differences in K mean and Q values of the frontal corneal parameters, as well as in Kmax, AC angle, RM, back, and front astigmatism, between stage 1 keratoconic and normal Caucasian eyes with steep cornea. All other parameters such as K mean and Q values of the back corneal parameters, Max FE, Max BE, ACD, ChV, and CV showed significant differences between the groups (P<0.05 for all. Conclusion: Scheimpflug imaging is able to detect corneal morphological differences between stage 1 KC eyes and healthy eyes with

  1. Bardet-Biedl syndrome and Usher syndrome.

    Science.gov (United States)

    Koenig, Rainer

    2003-01-01

    Bardet-Biedl syndrome (BBS) and Usher syndrome (USH) are the most prevalent syndromic forms of retinitis pigmentosa (RP), together they make up almost a quarter of the patients with RP. BBS is defined by the association of retinopathy, obesity, hypogonadism, renal dysfunction, postaxial polydactyly and mental retardation. This clinically complex syndrome is genetically heterogeneous with linkage to more than 6 loci, and 4 genes have been cloned so far. Recent molecular data present evidence that, in some instances, the clinical manifestation of BBS requires recessive mutations in 1 of the 6 BBS loci plus one or two additional mutations in a second BBS locus (tri- or tetra-allelic inheritance). USH is characterized by the combination of congenital or early-onset sensorineural deafness, RP, and variable degrees of vestibular dysfunction. Each of the three clinical types is genetically heterogeneous: 7 loci have been mapped for type 1, three loci for type 2, and two loci for type 3. Currently, 6 USH genes (MYO7A, USH1C, CDH23, PCDH15, USH2A, USH3) have been identified. Pathogenetically, mutations of the USH1 genes seem to result in defects of auditory and retinal sensory cells, the USH 2 phenotype is caused by defects of extracellular matrix or cell surface receptor proteins, and USH3 may be due to synaptic disturbances. The considerable contribution of syndromic forms of RP requires interdisciplinary approaches to the clinical and diagnostic management of RP patients.

  2. Molecular studies of deletions at the human steroid sulfatase locus

    International Nuclear Information System (INIS)

    Shapiro, L.J.; Yen, P.; Pomerantz, D.; Martin, E.; Rolewic, L.; Mohandas, T.

    1989-01-01

    The human steroid sulfatase gene (STS) is located on the distal X chromosome short arm close to the pseudoautosomal region but in a segment of DNA that is unique to the X chromosome. In contrast to most X chromosome-encoded genes, STS expression is not extinguished during the process of X chromosome inactivation. Deficiency of STS activity produced the syndrome of X chromosome-linked ichthyosis, which is one of the most common inborn errors of metabolism in man. Approximately 90% of STS - individuals have large deletions at the STS locus. The authors and others have found that the end points of such deletions are heterogeneous in their location. One recently ascertained subject was observed to have a 40-kilobase deletion that is entirely intragenic, permitting the cloning and sequencing of the deletion junction. Studies of this patient and of other X chromosome sequences in other subjects permit some insight into the mechanism(s) responsible for generating frequent deletions on the short arm of the X chromosome

  3. Influence of the He-Ne laser in different irradiation regimes on the cornea cells after ionizing irradiation

    International Nuclear Information System (INIS)

    Bulyakova, N.V.

    1984-01-01

    A study was made on epithelium cells of the eye cornea in mices entering the first postradiation mitosis. The influence of laser rays acting in the course of each exposure during one and the same period of time, or continuously, or by pulses was compared. The effect of laser radiation was evaluated from the frequency of occurrence of cells with chromosomal aberrations, mitotic index, coefficient of mitosis phases. It has been established that pulse radiation of a helium-neon laser in a certain operation regime produces a sanitating effect on cells of eye cornea epithelium in white mice damaged by ionizing radiation. Cells being killed in the interphase were not revealed in epithelium of the eye cornea. It enables to conclude that the amount of aberrant mitoses decreases as a result of postradiation repair of cells damaged by ionizing radiation, but not as a result of their elimination

  4. Optics of the human cornea influence the accuracy of stereo eye-tracking methods: a simulation study.

    Science.gov (United States)

    Barsingerhorn, A D; Boonstra, F N; Goossens, H H L M

    2017-02-01

    Current stereo eye-tracking methods model the cornea as a sphere with one refractive surface. However, the human cornea is slightly aspheric and has two refractive surfaces. Here we used ray-tracing and the Navarro eye-model to study how these optical properties affect the accuracy of different stereo eye-tracking methods. We found that pupil size, gaze direction and head position all influence the reconstruction of gaze. Resulting errors range between ± 1.0 degrees at best. This shows that stereo eye-tracking may be an option if reliable calibration is not possible, but the applied eye-model should account for the actual optics of the cornea.

  5. Topical timolol with and without benzalkonium chloride: epithelial permeability and autofluorescence of the cornea in glaucoma.

    Science.gov (United States)

    de Jong, C; Stolwijk, T; Kuppens, E; de Keizer, R; van Best, J

    1994-04-01

    Epithelial permeability and autofluorescence of the cornea were determined by fluorophotometry in 21 patients with open-angle glaucoma or ocular hypertension using timolol medication with the preservative benzalkonium chloride (BAC) and 2 weeks after changing to timolol medication without BAC. The investigation was performed to determine whether removal of BAC would reduce toxic effects on the cornea and complaints of sensations of burning or dry eye. Corneal epithelial permeability decreased significantly after changing medication (mean decrease per patient 27%, P = 0.025). Corneal autofluorescence increased significantly after changing medication suggesting an alteration in corneal metabolism (mean increase per patient 6%, P = 0.003). Timolol without BAC was found to be as effective as timolol with BAC in reducing intraocular pressure (P = 0.4). Removal of BAC from timolol resulted in an improvement of corneal epithelial barrier function and in a reduction of complaints. The improvement was found to be proportional to the duration of the preceding BAC-containing therapy.

  6. Experimental study on the healing process following laser welding of the cornea.

    Science.gov (United States)

    Rossi, Francesca; Pini, Roberto; Menabuoni, Luca; Mencucci, Rita; Menchini, Ugo; Ambrosini, Stefano; Vannelli, Gabriella

    2005-01-01

    An experimental study evaluating the application of laser welding of the cornea and the subsequent healing process is presented. The welding of corneal wounds is achieved after staining the cut walls with a solution of the chromophore indocyanine green, and irradiating them with a diode laser (810 nm) operating at low power (60 to 90 mW). The result is a localized heating of the cut, inducing controlled welding of the stromal collagen. In order to optimize this technique and to study the healing process, experimental tests, simulating cataract surgery and penetrating keratoplasty, were performed on rabbits: conventional and laser-induced suturing of corneal wounds were thus compared. A follow-up study 7 to 90 days after surgery was carried out by means of objective and histological examinations, in order to optimize the welding technique and to investigate the subsequent healing process. The analyses of the laser-welded corneas evidenced a faster and more effective restoration of the architecture of the stroma. No thermal damage of the welded stroma was detected, nor were there foreign body reactions or other inflammatory processes. Copyright 2005 Society of Photo-Optical Instrumentation Engineers.

  7. The ultrastructural alterations in rat corneas with experimentally-induced diabetes mellitus

    International Nuclear Information System (INIS)

    Take, G.; Karabay, G.; Erdogan, D.; Duyar, I.

    2006-01-01

    To examine the ultrastructural changes of rat corneas in streptozotocin (STZ) induced diabetes mellitus and the and the follow-up insulin treatment. Sprague-Dawley type rats were used for experimental procedures during the period from January to April 2003 at Baskent University, Ankara, Turkey. Rats were studied in four groups: group 1: controls, group 2 sham controls (single dose IV sodium citrate); group 3 STZ-induced diabetes mellitus (Single dose 45mg/kg STZ intravenously), group 4: diabetes mellitus + insulin treatment (8U/day). We observed degenerative changes in the epithelial layer, stromal keratocytes and endothelial cells in diabetic group. In contrast, the corneal layers have revealed positive alterations in the insulin-treated group. The statistical analysis, showed significant narrowing in the epithelial layer in the diabetic group (p0.02), whereas thickening was observed in the epithelial basement membrane and Descemet's membrane (p=0.002). It was determined that that diabetes mellitus causes degenerative changes in cornea, which are positively influenced by short-term insulin treatment. (author)

  8. Biofunctionalized Lysophosphatidic Acid/Silk Fibroin Film for Cornea Endothelial Cell Regeneration

    Science.gov (United States)

    Jeon, Hayan; Oliveira, Joaquim Miguel; Reis, Rui Luis; Khang, Gilson

    2018-01-01

    Cornea endothelial cells (CEnCs) tissue engineering is a great challenge to repair diseased or damaged CEnCs and require an appropriate biomaterial to support cell proliferation and differentiation. Biomaterials for CEnCs tissue engineering require biocompatibility, tunable biodegradability, transparency, and suitable mechanical properties. Silk fibroin-based film (SF) is known to meet these factors, but construction of functionalized graft for bioengineering of cornea is still a challenge. Herein, lysophosphatidic acid (LPA) is used to maintain and increase the specific function of CEnCs. The LPA and SF composite film (LPA/SF) was fabricated in this study. Mechanical properties and in vitro studies were performed using a rabbit model to demonstrate the characters of LPA/SF. ATR-FTIR was characterized to identify chemical composition of the films. The morphological and physical properties were performed by SEM, AFM, transparency, and contact angle. Initial cell density and MTT were performed for adhesion and cell viability in the SF and LPA/SF film. Reverse transcription polymerase chain reactions (RT-PCR) and immunofluorescence were performed to examine gene and protein expression. The results showed that films were designed appropriately for CEnCs delivery. Compared to pristine SF, LPA/SF showed higher biocompatibility, cell viability, and expression of CEnCs specific genes and proteins. These indicate that LPA/SF, a new biomaterial, offers potential benefits for CEnCs tissue engineering for regeneration. PMID:29710848

  9. Control of Scar Tissue Formation in the Cornea: Strategies in Clinical and Corneal Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Samantha L. Wilson

    2012-09-01

    Full Text Available Corneal structure is highly organized and unified in architecture with structural and functional integration which mediates transparency and vision. Disease and injury are the second most common cause of blindness affecting over 10 million people worldwide. Ninety percent of blindness is permanent due to scarring and vascularization. Scarring caused via fibrotic cellular responses, heals the tissue, but fails to restore transparency. Controlling keratocyte activation and differentiation are key for the inhibition and prevention of fibrosis. Ophthalmic surgery techniques are continually developing to preserve and restore vision but corneal regression and scarring are often detrimental side effects and long term continuous follow up studies are lacking or discouraging. Appropriate corneal models may lead to a reduced need for corneal transplantation as presently there are insufficient numbers or suitable tissue to meet demand. Synthetic optical materials are under development for keratoprothesis although clinical use is limited due to implantation complications and high rejection rates. Tissue engineered corneas offer an alternative which more closely mimic the morphological, physiological and biomechanical properties of native corneas. However, replication of the native collagen fiber organization and retaining the phenotype of stromal cells which prevent scar-like tissue formation remains a challenge. Careful manipulation of culture environments are under investigation to determine a suitable environment that simulates native ECM organization and stimulates keratocyte migration and generation.

  10. Effect of biometric characteristics on biomechanical properties of the cornea in cataract patient.

    Science.gov (United States)

    Song, Xue-Fei; Langenbucher, Achim; Gatzioufas, Zisis; Seitz, Berthold; El-Husseiny, Moatasem

    2016-01-01

    To determine the impact of biometric characteristics on the biomechanical properties of the human cornea using the ocular response analyzer (ORA) and standard comprehensive ophthalmic examinations before and after standard phacoemulsification. This study comprised 54 eyes with cataract with significant lens opacification in stages I or II that underwent phacoemulsification (2.8 mm incision). Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured by ORA preoperatively and at 1mo postoperatively. Biometric characteristics were derived from corneal topography [TMS-5, anterior equivalent (EQTMS) and cylindric (CYLTMS) power], corneal tomography [Casia, anterior and posterior equivalent (EQaCASIC, EQpCASIA) and cylindric (CYLaCASIA, CYLpCASIA) power], keratometry [IOLMaster, anterior equivalent (EQIOL) and cylindric (CYLIOL) power] and autorefractor [anterior equivalent (EQAR)]. Results from ORA were analyzed and correlated with those from all other examinations taken at the same time point. Preoperatively, CH correlated with EQpCASIA and CYLpCASIA only (P=0.001, P=0.002). Postoperatively, IOPg and IOPcc correlated with all equivalent powers (EQTMS, EQIOL, EQAR, EQaCASIA and EQpCASIA) (P=0.001, P=0.007, P=0.001, P=0.015, P=0.03 for IOPg and PBiometric characteristics may significantly affect biomechanical properties of the cornea in terms of CH, IOPcc and IOPg before, but even more after cataract surgery.

  11. The comparative safety of genipin versus UVA-riboflavin crosslinking of rabbit corneas

    Science.gov (United States)

    Song, Wenjing; Tang, Yun; Qiao, Jing; Li, Haili; Rong, Bei; Yang, Songlin; Wu, Yuan

    2017-01-01

    Purpose To investigate, after 24 h, the safety of genipin or ultraviolet A (UVA)-riboflavin crosslinking of keratocytes and endothelial cells. Methods Fifteen New Zealand white rabbits were selected and divided into a PBS group (five rabbits), a 0.2% genipin crosslinking (GP-CXL) group (five rabbits), and a UVA-riboflavin crosslinking (UVA-CXL) group (five rabbits). In the GP-CXL and PBS groups, 0.2% genipin or PBS was applied to the corneal surface of the right eyes. In the UVA-CXL group, a clinical crosslinking procedure was used. Before and after surgery, the operated eyes of each group were characterized with confocal microscopy, and the corneal buttons were excised for endothelium staining and electron microscopy. Results The corneal endothelial cell density of the GP-CXL, UVA-CLX, and PBS groups changed. There was a statistically significant difference in thickness and changes in corneal endothelial cell density between the UVA-CXL group and the PBS group (pUVA-CXL group and the GP-CXL group (pUVA-CXL group. In the GP-CXL group, only active keratocytes were found and minimal endothelial cell damage. Conclusions Treatment of rabbit corneas with 0.2% genipin showed minimal toxicity toward keratocytes and endothelial cells. Genipin is safer than UVA-CXL for crosslinking of thin corneas. PMID:28761323

  12. Colocalization of Galectin-3 With CD147 Is Associated With Increased Gelatinolytic Activity in Ulcerating Human Corneas.

    Science.gov (United States)

    Cruzat, Andrea; Gonzalez-Andrades, Miguel; Mauris, Jérôme; AbuSamra, Dina B; Chidambaram, Preethi; Kenyon, Kenneth R; Chodosh, James; Dohlman, Claes H; Argüeso, Pablo

    2018-01-01

    Galectin-3 is a carbohydrate-binding protein known to promote expression of matrix metalloproteinases, a hallmark of ulceration, through interaction with the extracellular matrix metalloproteinase inducer CD147. The aim of this study was to investigate the distribution of galectin-3 in corneas of patients with ulcerative keratitis and to determine its relationship to CD147 and the presence of gelatinolytic activity. This was an observational case series involving donor tissue from 13 patients with active corneal ulceration and 6 control corneas. Fixed-frozen sections of the corneas were processed to localize galectin-3 and CD147 by immunofluorescence microscopy. Gelatinolytic activity was detected by in situ zymography. Tissue from patients with active corneal ulceration showed a greater galectin-3 immunoreactivity in basal epithelia and stroma compared with controls. Immunofluorescence grading scores revealed increased colocalization of galectin-3 and CD147 in corneal ulcers at the epithelial-stromal junction and within fibroblasts. Quantitative analysis using the Manders' colocalization coefficient demonstrated significant overlap in corneas from patients with ulcerative keratitis (M1 = 0.29; M2 = 0.22) as opposed to control corneas (M1 = 0.01, P < 0.01; M2 = 0.02, P < 0.05). In these experiments, there was a significant positive correlation between the degree of galectin-3 and CD147 colocalization and the presence of gelatinolytic activity. Our results indicate that concomitant stimulation and colocalization of galectin-3 with CD147 are associated with increased gelatinolytic activity in the actively ulcerating human cornea and suggest a mechanism by which galectin-3 may contribute to the degradation of extracellular matrix proteins during ulceration.

  13. Locus of control and online learning

    Directory of Open Access Journals (Sweden)

    Suretha Esterhuysen

    2004-10-01

    Full Text Available The integration of online learning in university courses is considered to be both inevitable and necessary. Thus there is an increasing need to raise awareness among educators and course designers about the critical issues impacting on online learning. The aim of this study, therefore, was to assess the differences between two groups of first-year Business Sciences learners (online and conventional learners in terms of biographic and demographic characteristics and locus of control. The study population consisted of 586 first-year learners of whom 185 completed the Locus of Control Inventory (LCI. The results show that the two groups of learners do not differ statistically significantly from each other with respect to locus of control. The findings and their implications are also discussed. Opsomming Die integrasie van aanlyn-leer in universiteitskursusse word beskou as sowel onafwendbaar as noodsaaklik. Daar is dus ’n toenemende behoefte om bewustheid onder opvoedkundiges en kursusontwerpers te kweek oor die kritiese aspekte wat ’n impak op aanlyn-leer het (Morgan, 1996. Daarom was die doel van hierdie ondersoek om die verskille tussen twee groepe eerstejaarleerders in Bestuurs- en Ekonomiese Wetenskap (aanlyn en konvensionele leerders te bepaal ten opsigte van biografiese en demografiese eienskappe en lokus van beheer. Die populasie het bestaan uit 586 eerstejaarleerders waarvan 185 die Lokus van Beheer Vraelys voltooi het. Die resultate toon dat die twee groepe leerders nie statisties beduidend van mekaar verskil het met betrekking tot lokus van beheer nie. Die bevindinge en implikasies word ook bespreek.

  14. Designing Epigenome Editors: Considerations of Biochemical and Locus Specificities.

    Science.gov (United States)

    Sen, Dilara; Keung, Albert J

    2018-01-01

    The advent of locus-specific protein recruitment technologies has enabled a new class of studies in chromatin biology. Epigenome editors enable biochemical modifications of chromatin at almost any specific endogenous locus. Their locus specificity unlocks unique information including the functional roles of distinct modifications at specific genomic loci. Given the growing interest in using these tools for biological and translational studies, there are many specific design considerations depending on the scientific question or clinical need. Here we present and discuss important design considerations and challenges regarding the biochemical and locus specificities of epigenome editors. These include how to account for the complex biochemical diversity of chromatin; control for potential interdependency of epigenome editors and their resultant modifications; avoid sequestration effects; quantify the locus specificity of epigenome editors; and improve locus specificity by considering concentration, affinity, avidity, and sequestration effects.

  15. Cut Locus Construction using Deformable Simplicial Complexes

    DEFF Research Database (Denmark)

    Misztal, Marek Krzysztof; Bærentzen, Jakob Andreas; Anton, François

    2011-01-01

    In this paper we present a method for appproximating cut loci for a given point p on Riemannian 2D manifolds, closely related to the notion of Voronoi diagrams. Our method finds the cut locus by advecting a front of points equally distant from p along the geodesics originating at p and finding...... the domain to have disk topology. We test our method for tori of revolution and compare our results to the benchmark ones from [2]. The method, however, is generic and can be easily adapted to construct cut loci for other manifolds of genera other than 1....

  16. The effect of radiation and cystamine on the ability of the eye to induce the cornea in the intact skin

    International Nuclear Information System (INIS)

    Popov, D.V.; Starodubov, S.M.

    1975-01-01

    Common frog tadpoles (with and without cystamine protection) were subjected to whole-body irradiation (700 R) and skin transplanted from the back of donors to the site of the outer cornea of the right eye of the recipients. Secondary cornea induction in non-irradiated skin transplanted to the eye was then studied. It was found that a dose of 700 R completely suppresses the induction capacity of the eye, while cystamine protects it to 47.8%. It was also shown that the irradiation of tadpoles with X-rays slows down their general development, but that, with cystamine protection, their development rate remains normal. (V.A.P.)

  17. Quantifying the effects of UV-A/riboflavin crosslinking on the elastic anisotropy and hysteresis of the porcine cornea by noncontact optical coherence elastography

    Science.gov (United States)

    Singh, Manmohan; Li, Jiasong; Raghunathan, Raksha; Han, Zhaolong; Nair, Achuth; Liu, Chih-Hao; Aglyamov, Salavat R.; Twa, Michael D.; Larin, Kirill V.

    2017-02-01

    The collagen fibril orientation of the cornea can provide critical information about cornea tissue health because diseases such as keratoconus and therapeutic interventions such as UV-A/riboflavin corneal collagen crosslinking (CXL) can alter the ultrastructural arrangement of collagen fibrils. Here, we quantify the elastic anisotropy and hysteresis of in situ porcine corneas as a function of intraocular pressure (IOP) with noncontact optical coherence elastography. Moreover, the effects of UV-A riboflavin corneal collagen crosslinking on the elastic anisotropy and hysteresis were evaluated. The propagation of an air-pulse induced elastic wave was imaged at stepped meridional angles by a home built phasestabilized swept source OCE system. The stiffness of the cornea was translated from the velocity of the wave, and the elastic anisotropy was quantified by modifying the planar anisotropy coefficient. As the IOP increased, the stiffness of the corneas increased from 18 kPa at 15 mmHg IOP to 120 kPa at 30 mmHg IOP. While there was a measureable hysteresis, it was not significant. After CXL, the Young's modulus of the corneas significantly increased from 18 kPa to 44 kPa at 15 mmHg IOP. The mechanical anisotropy also increased significantly from 10 a.u. in the untreated corneas to 23 a.u. in the CXL treated corneas, 15 mmHg IOP. However, CXL did not change the elastic anisotropic orientation, and the mechanical anisotropic hysteresis was not significant after CXL.

  18. An active artificial cornea with the function of inducing new corneal tissue generation in vivo-a new approach to corneal tissue engineering

    International Nuclear Information System (INIS)

    Huang Yaoxiong; Li Qinhua

    2007-01-01

    An active artificial cornea which can perform the function of inducing new cornea generation in vivo but does not need culture cells in vitro and which has similar optical and mechanical properties to those of the human cornea was constructed. An animal keratoplasty experiment using the artificial cornea as the implant showed that the animals' corneas could keep smooth surface and clear stroma postoperatively, and that the repopulation of the host's keratocytes, the degradation of the implant and new corneal tissue generation were completed at 5-6 months after surgery. Such an artificial cornea has several advantages over other corneal equivalents constructed in the typical way of tissue engineering: in having similar mechanical and optical properties to those of the human cornea and with no exogenetic cells, it can be used universally in different implantation surgeries without immunoreaction; it is easy to prepare and process into different shapes and sizes on a large scale, and suitable for long-distance transportation and long-term storage. All these characteristics make it a new approach to cornea tissue engineering having potential in many clinical applications

  19. Relationships between locus of control and paranormal beliefs.

    Science.gov (United States)

    Newby, Robert W; Davis, Jessica Boyette

    2004-06-01

    The present study investigated the associations between scores on paranormal beliefs, locus of control, and certain psychological processes such as affect and cognitions as measured by the Linguistic Inquiry and Word Count. Analysis yielded significant correlations between scores on Locus of Control and two subscales of Tobacyk's (1988) Revised Paranormal Beliefs Scale, New Age Philosophy and Traditional Paranormal Beliefs. A step-wise multiple regression analysis indicated that Locus of Control was significantly related to New Age Philosophy. Other correlations were found between Tobacyk's subscales, Locus of Control, and three processes measured by the Linguistic Inquiry and Word Count.

  20. Impact of locus of control on health message effectiveness.

    Science.gov (United States)

    Kong, Ying; Shen, Fuyuan

    2011-10-01

    This article examined how individuals' locus of control might moderate the effect of health message frames. An experiment was conducted whereby participants read either individual- or social-responsibility message frames after their locus of control was primed. Results indicated that messages presented in individual-responsibility frames were more persuasive when people were primed with internal locus of control, whereas social-responsibility framed appeals were more persuasive when people were primed with external locus of control. These results were found for individuals in both high and low cognitive load conditions. Theoretical and practical implications of the findings are discussed.

  1. Beals Syndrome

    Science.gov (United States)

    ... the syndrome. How does Beals syndrome compare with Marfan syndrome? People with Beals syndrome have many of the ... bone) and aortic enlargement problems as people with Marfan syndrome, and treatments for these problems are the same. ...

  2. Brown-McLean Syndrome in a Pediatric Patient

    Science.gov (United States)

    Tourkmani, Abdo Karim; Martinez, Jaime D.; Berrones, David; Juárez-Domínguez, Brenda Y.; Beltrán, Francisco; Galor, Anat

    2015-01-01

    The purpose of this manuscript is to report the case of a 12-year-old patient who presented for routine ophthalmic examination after congenital cataract surgery performed at 2 months of age. The patient was diagnosed with bilateral Brown-McLean syndrome by slit lamp examination. No treatment was required because the patient was asymptomatic and had a clear central cornea. This is the first described case of Brown-McLean syndrome in a pediatric patient, representing the importance of clinical examination in the pediatric age group after cataract surgery because of the risk for patients of developing peripheral edema. PMID:26034485

  3. Partial Denervation of Subbasal Axons Persists Following Debridement Wounds to the Mouse Cornea

    Science.gov (United States)

    Pajoohesh-Ganji, Ahdeah; Pal-Ghosh, Sonali; Tadvalkar, Gauri; Kyne, Briana M.; Saban, Daniel R.; Stepp, Mary Ann

    2015-01-01

    Although sensory reinnervation occurs after injury in the PNS, poor reinnervation in the elderly and those with diabetes often leads to pathology. Here we quantify subbasal axon density in the central and peripheral mouse cornea over time after three different types of injury. The mouse cornea is highly innervated with a dense array of subbasal nerves that form a spiral called the vortex at the corneal center or apex; these nerves are readily detected within flat mounted corneas. After anesthesia, corneal epithelial cells were removed using either a dulled blade or a rotating burr within an area demarcated centrally with a 1.5 mm trephine. A third wound type, superficial trephination, involved demarcating the area with the 1.5 mm trephine but not removing cells. By 7d after superficial trephination, subbasal axon density returns to control levels; by 28d the vortex reforms. Although axon density is similar to control 14d after dulled blade and rotating burr wounding, defects in axon morphology at the corneal apex remain. After 14d, axons retract from the center leaving the subbasal axon density reduced by 37.2% and 36.8% at 28d after dulled blade and rotating burr wounding, respectively, compared to control. Assessment of inflammation using flow cytometry shows that persistent inflammation is not a factor in the incomplete reinnervation. Expression of mRNAs encoding 22 regeneration associated genes (RAGs) involved in axon targeting assessed by QPCR reveals that netrin-1 and ephrin signaling are altered after wounding. Subpopulations of corneal epithelial basal cells at the corneal apex stop expressing ki67 as early as 7d after injury and by 14d and 28d after wounding, many of these basal cells undergo apoptosis and die. While subbasal axons are restored to their normal density and morphology after superficial trephination, subbasal axon recovery is partial after debridement wounds. The increase in corneal epithelial basal cell apoptosis at the apex observed at 14d

  4. Partial denervation of sub-basal axons persists following debridement wounds to the mouse cornea.

    Science.gov (United States)

    Pajoohesh-Ganji, Ahdeah; Pal-Ghosh, Sonali; Tadvalkar, Gauri; Kyne, Briana M; Saban, Daniel R; Stepp, Mary Ann

    2015-11-01

    Although sensory reinnervation occurs after injury in the peripheral nervous system, poor reinnervation in the elderly and those with diabetes often leads to pathology. Here we quantify sub-basal axon density in the central and peripheral mouse cornea over time after three different types of injury. The mouse cornea is highly innervated with a dense array of sub-basal nerves that form a spiral called the vortex at the corneal center or apex; these nerves are readily detected within flat mounted corneas. After anesthesia, corneal epithelial cells were removed using either a dulled blade or a rotating burr within an area demarcated centrally with a 1.5 mm trephine. A third wound type, superficial trephination, involved demarcating the area with the 1.5 mm trephine but not removing cells. By 7 days after superficial trephination, sub-basal axon density returns to control levels; by 28 days the vortex reforms. Although axon density is similar to control 14 days after dulled blade and rotating burr wounding, defects in axon morphology at the corneal apex remain. After 14 days, axons retract from the center leaving the sub-basal axon density reduced by 37.2 and 36.8% at 28 days after dulled blade and rotating burr wounding, respectively, compared with control. Assessment of inflammation using flow cytometry shows that persistent inflammation is not a factor in the incomplete reinnervation. Expression of mRNAs encoding 22 regeneration-associated genes involved in axon targeting assessed by QPCR reveals that netrin-1 and ephrin signaling are altered after wounding. Subpopulations of corneal epithelial basal cells at the corneal apex stop expressing ki67 as early as 7 days after injury and by 14 and 28 days after wounding, many of these basal cells undergo apoptosis and die. Although sub-basal axons are restored to their normal density and morphology after superficial trephination, sub-basal axon recovery is partial after debridement wounds. The increase in corneal

  5. Photorefractive Keratectomy (PRK) is Safe and Effective for Patients with Myopia and Thin Corneas.

    Science.gov (United States)

    Naderi, Mostafa; Ghadamgahi, Saeed; Jadidi, Khosrow

    2016-01-01

    The aim of this study was to evaluate the long-term safety and efficacy of photorefractive keratectomy (PRK) for patients with myopia and thin corneas. In this retrospective case series, we included 74 eyes of 38 patients with myopia and central corneal thickness (CCT) PRK and had a mean postoperative follow-up period of four years. The following factors were evaluated: CCT, refraction, uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), ablation depth, safety and efficacy indices (i.e., the ratio of the mean postoperative BCVA to the mean preoperative BCVA, and the ratio of the mean postoperative UCVA to mean preoperative the BCVA, respectively), and evidence of corneal ectasia (based on Orbscan topography images).The patients were aged 20 - 46 years (mean ±SD age, 28.18± 6.82 years). The mean ± SD pre- and postoperative CCTwas485.92 ± 9.27 µm and 434.84 ± 20.48 µm, respectively. The mean ± SD pre- and postoperative myopia was -2.77 D ± 1.51 and -0.24 ± 0.39 D, respectively, and the mean ± SD pre- and postoperative astigmatism was -0.82 D ± 0.99 and -0.37 ± 0.37 D, respectively. The mean pre- and postoperative BCVA and postoperative UCVA was 0.011 ± 0.03 Logarithm of the Minimum Angle of Resolution (log MAR), 0.003 ± 0.01 log MAR, and 0.054 ± 0.09 log MAR, respectively. The mean ± SD ablation depth, safety index and efficacy index was 54.34 ± 16.28 µm, 0.02 ± 0.12, and 0.11 ± 0.50, respectively. Regarding the postoperative corneal clarity, 72 eyes (97.3%) had a clear cornea (grade 0) and the remaining two eyes of one patient (2.70%) had a trace haze (grade 1). There was no evidence of corneal ectasia on any of the Orbscan topography images. Thus, among patients with myopia and thin corneas (PRK seems to be acceptable in terms of both safety and efficacy 4 years after surgery, based on the stability of postoperative refraction, visual acuity, and topographic outcomes, and outcomes based on the safety and efficacy indexes.

  6. Fibre optic spectrophotometry for the in vitro evaluation of ultraviolet radiation (UVR) spectral transmittance of rabbit corneas

    International Nuclear Information System (INIS)

    Walsh, J E; Fleming, D P; Bergmanson, J P G; Koehler, L V; Doughty, M J; Harmey, J H

    2008-01-01

    A fibre optic spectrophotometer front-end system for measuring corneas to overcome shortcomings associated with existing instruments was tested. The system allowed prompt measurement postmortem, minimizing beam pathlength to reduce the effects of scatter and unwanted refraction and eliminated optical interfaces and cuvette media. Rabbit corneas were excised immediately postmortem and placed on a detecting fibre optic coupled to an Ocean Optics spectrophotometer and illuminated by a deuterium–halogen source. The compact instrument with its small beam size allowed tissue profiling at test points across the corneal surface and efficient interchange for comparison of different tissues. This simplified system operation allowed rapid tissue altering to study induced changes on transmittance. The corneal transmittance data showed a consistent sharp cut-off at 320 nm in the ultraviolet radiation (UVR) spectrum, which decayed rapidly from postmortem swelling. Inter- and intra-corneal consistency was demonstrated by comparing data from different regions of the same cornea and those from opposite eyes. Changes to the spectra, particularly in the UVB below 300 nm, were evident when the corneal epithelium was removed, indicating that this layer is not the only corneal UVR filter. The new system reduced much of the variability associated with previous methods, as it rapidly measured corneal transmittance postmortem. Data are in broad agreement with published transmittance curves. The removal of the corneal epithelium revealed a substantial stromal contribution to the overall corneal UVR absorption, suggesting that corneas with pathologically or iatrogenically thinned stromas are less effective UVR blockers

  7. The tissue-engineered human cornea as a model to study expression of matrix metalloproteinases during corneal wound healing.

    Science.gov (United States)

    Couture, Camille; Zaniolo, Karine; Carrier, Patrick; Lake, Jennifer; Patenaude, Julien; Germain, Lucie; Guérin, Sylvain L

    2016-02-01

    Corneal injuries remain a major cause of consultation in the ophthalmology clinics worldwide. Repair of corneal wounds is a complex mechanism that involves cell death, migration, proliferation, differentiation, and extracellular matrix (ECM) remodeling. In the present study, we used a tissue-engineered, two-layers (epithelium and stroma) human cornea as a biomaterial to study both the cellular and molecular mechanisms of wound healing. Gene profiling on microarrays revealed important alterations in the pattern of genes expressed by tissue-engineered corneas in response to wound healing. Expression of many MMPs-encoding genes was shown by microarray and qPCR analyses to increase in the migrating epithelium of wounded corneas. Many of these enzymes were converted into their enzymatically active form as wound closure proceeded. In addition, expression of MMPs by human corneal epithelial cells (HCECs) was affected both by the stromal fibroblasts and the collagen-enriched ECM they produce. Most of all, results from mass spectrometry analyses provided evidence that a fully stratified epithelium is required for proper synthesis and organization of the ECM on which the epithelial cells adhere. In conclusion, and because of the many characteristics it shares with the native cornea, this human two layers corneal substitute may prove particularly useful to decipher the mechanistic details of corneal wound healing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. 3D refraction correction and extraction of clinical parameters from spectral domain optical coherence tomography of the cornea.

    Science.gov (United States)

    Zhao, Mingtao; Kuo, Anthony N; Izatt, Joseph A

    2010-04-26

    Capable of three-dimensional imaging of the cornea with micrometer-scale resolution, spectral domain-optical coherence tomography (SDOCT) offers potential advantages over Placido ring and Scheimpflug photography based systems for accurate extraction of quantitative keratometric parameters. In this work, an SDOCT scanning protocol and motion correction algorithm were implemented to minimize the effects of patient motion during data acquisition. Procedures are described for correction of image data artifacts resulting from 3D refraction of SDOCT light in the cornea and from non-idealities of the scanning system geometry performed as a pre-requisite for accurate parameter extraction. Zernike polynomial 3D reconstruction and a recursive half searching algorithm (RHSA) were implemented to extract clinical keratometric parameters including anterior and posterior radii of curvature, central cornea optical power, central corneal thickness, and thickness maps of the cornea. Accuracy and repeatability of the extracted parameters obtained using a commercial 859nm SDOCT retinal imaging system with a corneal adapter were assessed using a rigid gas permeable (RGP) contact lens as a phantom target. Extraction of these parameters was performed in vivo in 3 patients and compared to commercial Placido topography and Scheimpflug photography systems. The repeatability of SDOCT central corneal power measured in vivo was 0.18 Diopters, and the difference observed between the systems averaged 0.1 Diopters between SDOCT and Scheimpflug photography, and 0.6 Diopters between SDOCT and Placido topography.

  9. In vivo imaging through the entire thickness of human cornea by full-field optical coherence tomography

    Science.gov (United States)

    Mazlin, Viacheslav; Xiao, Peng; Dalimier, Eugénie; Grieve, Kate; Irsch, Kristina; Sahel, José; Fink, Mathias; Boccara, Claude

    2018-02-01

    Despite obvious improvements in visualization of the in vivo cornea through the faster imaging speeds and higher axial resolutions, cellular imaging stays unresolvable task for OCT, as en face viewing with a high lateral resolution is required. The latter is possible with FFOCT, a method that relies on a camera, moderate numerical aperture (NA) objectives and an incoherent light source to provide en face images with a micrometer-level resolution. Recently, we for the first time demonstrated the ability of FFOCT to capture images from the in vivo human cornea1. In the current paper we present an extensive study of appearance of healthy in vivo human corneas under FFOCT examination. En face corneal images with a micrometer-level resolution were obtained from the three healthy subjects. For each subject it was possible to acquire images through the entire corneal depth and visualize the epithelium structures, Bowman's layer, sub-basal nerve plexus (SNP) fibers, anterior, middle and posterior stroma, endothelial cells with nuclei. Dimensions and densities of the structures visible with FFOCT, are in agreement with those seen by other cornea imaging methods. Cellular-level details in the images obtained together with the relatively large field-of-view (FOV) and contactless way of imaging make this device a promising candidate for becoming a new tool in ophthalmological diagnostics.

  10. A human hemi-cornea model for eye irritation testing: quality control of production, reliability and predictive capacity.

    Science.gov (United States)

    Engelke, M; Zorn-Kruppa, M; Gabel, D; Reisinger, K; Rusche, B; Mewes, K R

    2013-02-01

    We have developed a 3-dimensional human hemi-cornea which comprises an immortalized epithelial cell line and keratocytes embedded in a collagen stroma. In the present study, we have used MTT reduction of the whole tissue to clarify whether the production of this complex 3-D-model is transferable into other laboratories and whether these tissues can be constructed reproducibly. Our results demonstrate the reproducible production of the hemi-cornea model according to standard operation procedures using 15 independent batches of reconstructed hemi-cornea models in two independent laboratories each. Furthermore, the hemi-cornea tissues have been treated with 20 chemicals of different eye-irritating potential under blind conditions to assess the performance and limitations of our test system comparing three different prediction models. The most suitable prediction model revealed an overall in vitro-in vivo concordance of 80% and 70% in the participating laboratories, respectively, and an inter-laboratory concordance of 80%. Sensitivity of the test was 77% and specificity was between 57% and 86% to discriminate classified from non-classified chemicals. We conclude that additional physiologically relevant endpoints in both epithelium and stroma have to be developed for the reliable prediction of all GHS classes of eye irritation in one stand alone test system. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Case report: a novel KERA mutation associated with cornea plana and its predicted effect on protein function

    DEFF Research Database (Denmark)

    Roos, Laura; Bertelsen, Birgitte; Harris, Pernille

    2015-01-01

    of the keratocan gene (KERA) on chromosome 12q22. To date, only nine different disease-associated KERA mutations, including four missense mutations, have been described. Case presentation: In this report, we present clinical data from a Turkish family with autosomal recessive cornea plana. In some of the affected...

  12. Specific demographic factors could predict deceased potential cornea donors: A retrospective study from Beijing Tongren Hospital Eye Bank.

    Science.gov (United States)

    Liu, Yang; Zhang, Yingnan; Zhang, Jing; Yu, Jin; Liang, Qingfeng; Pan, Zhiqiang

    2017-12-01

    Compared with evident cornea donors (ECDs), deceased potential cornea donors (DPCDs) have no obvious donor identifications to reference, which causes many eligible cornea tissues to be wasted. The demographic characteristics of DPCDs might be different from those of ECDs owing to the following different features: donation consent provided by relatives and willingness to donate before death. Thus, the aim of this study is to reveal the demographic characteristics of DPCDs by comparing DPCDs and ECDs.The demographic factors of 138 donors (both DPCDs and ECDs) were collected from the Beijing Tongren Hospital Eye Bank database and analyzed. To differentiate DPCDs from ECDs using the above-mentioned features, we interviewed the relatives of the donors by telephone. The relatives' attitudes toward cornea donation and their suggestions for our donation service were also acquired during the interview. Two logistic regressions were performed to reveal the demographic factors influencing the 2 features and indicate DPCDs.The donors had certain demographic characteristics (elderly, secondary, or tertiary education level, central district resident), and the most frequent cause of death for the donors was a malignant tumor (n = 56, 43.1%). All the relatives had positive attitudes toward cornea donations, and they hoped to increase publicity efforts to encourage more people to donate and establish more convenient and efficient access for cornea donation. In univariate regressions, age (P = .004, >50 years: odds ratio [OR] = 6.89, 95% confidence interval [CI]: 1.82-26.05), marital status (P = .043, divorced: OR = 9.00,95% CI: 1.33-60.80) significantly influenced relative consent, whereas age (P = .001, >50 years: OR = 15.00, 95% CI: 3.00-74.98), and family address (P = .001, central district: OR = 1) were significant factors influencing the willingness to donate before death. In multivariate regression, age (P = .021, >50 years: OR = 8

  13. Optical coherence elastography assesses tissue modifications in laser reshaping of cornea and cartilages

    Science.gov (United States)

    Zaitsev, V. Y.; Matveyev, A. L.; Matveev, L. A.; Gelikonov, G. V.; Omelchenko, A. I.; Shabanov, D. V.; Sovetsky, A. A.; Baum, O. I.; Vitkin, A.; Sobol, E. N.

    2018-02-01

    Non-surgical thermo-mechanical reshaping of avascular collagenous tissues (cartilages and cornea) using moderate heating by IR-laser irradiation is an emerging technology that can find important applications in visioncorrection problems and preparation of cartilaginous implants in otolaryngology. To estimate both transient interframe strains and cumulative resultant strains produced by the laser irradiation of the tissue we use and improved version of strain mapping developed in our previous work related to compressional phase-sensitive optical coherence tomography. To reveal microstructural changes in the tissue regions where irradiation-produced strains do not disappear after temperature equilibration, we apply compressional optical coherence elastography in order to visualize the resultant variations in the tissue stiffness. The so-found regions of the stiffness reduction are attributed to formation of microscopic pores, existence of which agree with independent data obtained using methods of high-resolution microscopy.

  14. Locus - ASTRA | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data ...URL: ftp://ftp.biosciencedbc.jp/archive/astra/LATEST/astra_locus.zip File size: 887 KB Simple search URL htt...icing type (ex. cassette) About This Database Database Description Download License Update History of This Database Site Policy | Contact Us Locus - ASTRA | LSDB Archive ...

  15. Is this Red Spot the Blue Spot (locus ceruleum)?

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Won Sick; Lee, Yu Kyung; Lee, Min Kyung; Hwang, Kyung Hoon [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2010-06-15

    The authors report brain images of 18F-FDG-PET in a case of schizophrenia. The images showed strikingly increased bilateral uptake in the locus ceruleum. The locus ceruleum is called the blue spot and known to be a center of the norepinephrinergic system.

  16. Metacognition: As a Predictor of One's Academic Locus of Control

    Science.gov (United States)

    Arslan, Serhat; Akin, Ahmet

    2014-01-01

    The purpose of this study is to examine the effect of metacognition on one's academic locus of control. The study's sample group consists of 451 university students enrolled in various programs at Sakarya University, Turkey. In this study, the Metacognitive Awareness Inventory and the Academic Locus of Control Scale were used. The correlations and…

  17. Personality and Locus of Control among School Children

    Science.gov (United States)

    Pandya, Archana A.; Jogsan, Yogesh A.

    2013-01-01

    The main purpose of this investigation is to find out the sex differences in personality traits and locus of control among school children. A total 60 children (30 boys and 30 girls) were taken as a sample. The research tool for personality, children personality questionnaire was used, which was made by Cattell and Porter. Locus of control was…

  18. Physical Attractiveness, Locus of Control, Sex Role, and Conversational Assertiveness.

    Science.gov (United States)

    Campbell, Keith F.; And Others

    1990-01-01

    Analyzes the relationship among physical attractiveness, locus of control, sex role orientation, and assertiveness in undergraduate students. Reviews videotapes of mixed-sex student groups engaged in discussion. Finds an internal locus of control positively correlated with assertiveness. Uses a behavioral measure of assertiveness rather than…

  19. Locus of control and investment in risky assets

    NARCIS (Netherlands)

    Salamanca Acosta, N.; de Grip, A.; Fouarge, D.; Montizaan, R.M.

    2013-01-01

    Using representative household panel data, we show that the investment behavior of households is related to the economic locus of control of household heads. A household’s internal locus of control in economic issues is positively related to its decision to hold risky assets as well as its share of

  20. Locus of control and investment in risky assets

    NARCIS (Netherlands)

    Salamanca, N.; de Grip, A.; Fouarge, D.; Montizaan, R.M.

    2013-01-01

    Using representative household panel data, we show that the investment behavior of households is related to the economic locus of control of household heads. A household's internal locus of control in economic issues is positively related to its decision to hold risky assets as well as its share of

  1. Is this Red Spot the Blue Spot (locus ceruleum)?

    International Nuclear Information System (INIS)

    Choe, Won Sick; Lee, Yu Kyung; Lee, Min Kyung; Hwang, Kyung Hoon

    2010-01-01

    The authors report brain images of 18F-FDG-PET in a case of schizophrenia. The images showed strikingly increased bilateral uptake in the locus ceruleum. The locus ceruleum is called the blue spot and known to be a center of the norepinephrinergic system.

  2. Sphere-forming cells from peripheral cornea demonstrate a wound-healing response to injury.

    Science.gov (United States)

    Huang, Stephanie U; Yoon, Jinny J; Ismail, Salim; McGhee, Jennifer J; Sherwin, Trevor

    2015-11-01

    The cornea is the initial refractive interface of the eye. Its transparency is critical for clear vision and is maintained by stem cells which also act to repair injury inflicted by external insults, such as chemical and thermal burns. Damage to the epithelium compromises its clarity and can reduce or eliminate the stem cell population, diminishing the ability for self-repair. This condition has been termed "limbal stem cell deficiency"; severe cases can lead to corneal blindness. Sphere-forming cells isolated from peripheral cornea are a potential source of stem and progenitor cells for corneal repair. When provided with appropriate substrate, these spheres have the ability to adhere and for cells to migrate outwards akin to that of their natural environment. Direct compression injury and remote scratch injury experiments were conducted on the sphere cells to gauge their wound healing capacity. Measures of proliferation, differentiation, and migration were assessed by immunohistochemical detection of EdU incorporation, α-smooth muscle actin expression and confocal image analysis, respectively. Both modes of injury were observed to draw responses from the spheres indicating wound healing processes. Direct wounding induced a rapid, but transient increase in expression of α-SMA, a marker of corneal myofibroblasts, followed by a proliferative and increasing migratory response. The spheres were observed to respond to remote injury as entire units, with no directional response seen for targeted repair over the scratch injury area. These results give strength to the future use of these peripheral corneal spheres as transplantable units for the regeneration of corneal tissue. © 2015 International Federation for Cell Biology.

  3. Coupled biomechanical response of the cornea assessed by non-contact tonometry. A simulation study.

    Directory of Open Access Journals (Sweden)

    Miguel Á Ariza-Gracia

    Full Text Available The mechanical response of the cornea subjected to a non-contact air-jet tonometry diagnostic test represents an interplay between its geometry, the corneal material behavior and the loading. The objective is to study this interplay to better understand and interpret the results obtained with a non-contact tonometry test. A patient-specific finite element model of a healthy eye, accounting for the load free configuration, was used. The corneal tissue was modeled as an anisotropic hyperelastic material with two preferential directions. Three different sets of parameters within the human experimental range obtained from inflation tests were considered. The influence of the IOP was studied by considering four pressure levels (10-28 mmHg whereas the influence of corneal thickness was studied by inducing a uniform variation (300-600 microns. A Computer Fluid Dynamics (CFD air-jet simulation determined pressure loading exerted on the anterior corneal surface. The maximum apex displacement showed a linear variation with IOP for all materials examined. On the contrary, the maximum apex displacement followed a cubic relation with corneal thickness. In addition, a significant sensitivity of the apical displacement to the corneal stiffness was also obtained. Explanation to this behavior was found in the fact that the cornea experiences bending when subjected to an air-puff loading, causing the anterior surface to work in compression whereas the posterior surface works in tension. Hence, collagen fibers located at the anterior surface do not contribute to load bearing. Non-contact tonometry devices give useful information that could be misleading since the corneal deformation is the result of the interaction between the mechanical properties, IOP, and geometry. Therefore, a non-contact tonometry test is not sufficient to evaluate their individual contribution and a complete in-vivo characterization would require more than one test to independently determine

  4. Repeatability of pachymetric mapping using fourier domain optical coherence tomography in corneas with opacities.

    Science.gov (United States)

    Samy El Gendy, Nehal M; Li, Yan; Zhang, Xinbo; Huang, David

    2012-04-01

    To evaluate the repeatability of Fourier domain optical coherence tomography (OCT) pachymetric mapping in patients with corneal opacities and to assess the reliability of Fourier domain OCT with 830 nm wavelength as a pachymetric measurement tool in opaque corneas. A Fourier domain OCT system was used to map the corneal thickness of patients with corneal scars or dystrophy. A retrospective study of a consecutive series was conducted. The repeatability was measured using pooled standard deviation of repeated measurements. A slit-scanning tomography device provided pachymetric mapping for comparison. Seventeen eyes of 12 patients with corneal scars (7 trauma and 3 post infection) or dystrophy (2 Reis-Bucklers and 5 granular dystrophy) were included. The posterior corneal boundary was detectable in all cases. The average corneal thickness measured by OCT was 536 ± 89 μm in central 2 mm area, 553 ± 76 μm in pericentral 2- to 5-mm area, and 508 ± 93 μm for the minimum corneal thickness. The slit-scanning tomography central corneal thickness, 433 ± 111 μm, was significantly lower than OCT readings (mean difference -91.1 ± 33.3 μm, P = 0.002). Repeatability of the OCT measurements was 2.1 μm centrally and 1.2 μm pericentrally. Pachymetric mapping with Fourier domain OCT was highly repeatable. Fourier domain OCT is a reliable pachymetric tool in opaque corneas. In comparison, corneal thickness measured by the slit-scanning tomography is significantly thinner than those measured by the Fourier domain OCT in the presence of corneal opacities.

  5. Biomechanical responses of healthy and keratoconic corneas measured using a noncontact scheimpflug-based tonometer.

    Science.gov (United States)

    Ali, Noor Q; Patel, Dipika V; McGhee, Charles N J

    2014-05-15

    To examine the repeatability of measurements obtained using a noncontact Scheimpflug-based tonometer (Corvis ST) and investigate potential differences in these parameters between healthy and keratoconic (KC) corneas. Forty-five keratoconic eyes and 103 healthy eyes were examined using biomicroscopy, corneal tomography and the Corvis ST (CST). Intraocular pressure and central corneal thickness (CCT) were highly repeatable (intraclass correlation [ICC] > 0.70, coefficient of variation [CV] 0.60, CV < 0.20). There was no association between DA and age, sex, or ethnicity in healthy eyes. There was a greater mean DA in the KC group compared with 46 age-matched healthy eyes (KC 1.37 ± 0.21 mm, healthy 1.05 ± 0.11 mm, P < 0.001). Multivariate analysis showed DA in KC was predicted by IOP, CCT, and the steepest simulated keratometry value (P = 0.03, P = 0.03, P = 0.001 respectively, R(2) = 0.75). A subgroup analysis of healthy and KC eyes with comparable mean CCT and IOP highlighted a statistically significant difference in mean DA (KC 1.25 ± 0.08 mm, thin healthy 1.13 ± 0.09 mm, P = 0.006). Receiver-operating characteristic analysis showed an area under the curve of 0.77 (95% CI 0.61-0.93, P = 0.006) but no ideal cutoff value for DA. Key parameters assessed by the CST are repeatable. Keratoconus is associated with greater DA than in healthy eyes, even when controlled for CCT and IOP. Deformation amplitude may be a useful adjunct in keratoconus assessment and monitoring, but cannot solely discriminate between healthy and keratoconic corneas. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  6. In vivo laser confocal microscopy findings of a cornea with osteogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Kobayashi A

    2014-02-01

    Full Text Available Akira Kobayashi, Tomomi Higashide, Hideaki Yokogawa, Natsuko Yamazaki, Toshinori Masaki, Kazuhisa Sugiyama Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan Objective: To report the in vivo laser confocal microscopy findings of a cornea with osteogenesis imperfecta (OI with special attention to the abnormality of Bowman's layer and sub-Bowman's fibrous structures (K-structures. Patients and methods: Two patients (67-year-old male and his 26-year-old son with OI type I were included in this study. Slit lamp biomicroscopic and in vivo laser confocal microscopic examinations were performed for both patients. Central corneal thickness and central endothelial cell density were also measured. Results: Although the corneas looked clear with normal endothelial density for both eyes in both patients, they were quite thin (386 µm oculus dexter (OD (the right eye and 384 µm oculus sinister (OS (the left eye in the father and 430 µm OD and 425 µm OS in the son. In both patients, slit lamp biomicroscopic and in vivo laser confocal microscopic examination showed similar results. Anterior corneal mosaics produced by rubbing the eyelid under fluorescein were completely absent in both eyes. In vivo laser confocal microscopy revealed an absent or atrophic Bowman's layer; a trace of a presumed Bowman's layer and/or basement membrane was barely visible with high intensity. Additionally, K-structures were completely absent in both eyes. Conclusion: The absence of K-structures and fluorescein anterior corneal mosaics strongly suggested an abnormality of Bowman's layer in these OI patients. Keywords: osteogenesis imperfecta, K-structure, confocal microscopy, Bowman's layer

  7. Sustained Subconjunctival Delivery of Infliximab Protects the Cornea and Retina Following Alkali Burn to the Eye.

    Science.gov (United States)

    Zhou, Chengxin; Robert, Marie-Claude; Kapoulea, Vassiliki; Lei, Fengyang; Stagner, Anna M; Jakobiec, Frederick A; Dohlman, Claes H; Paschalis, Eleftherios I

    2017-01-01

    Tumor necrosis factor (TNF)-α is upregulated in eyes following corneal alkali injury and contributes to corneal and also retinal damage. Prompt TNF-α inhibition by systemic infliximab ameliorates retinal damage and improves corneal wound healing. However, systemic administration of TNF-α inhibitors carries risk of significant complications, whereas topical eye-drop delivery is hindered by poor ocular bioavailability and the need for patient adherence. This study investigates the efficacy of subconjunctival delivery of TNF-α antibodies using a polymer-based drug delivery system (DDS). The drug delivery system was prepared using porous polydimethylsiloxane/polyvinyl alcohol composite fabrication and loaded with 85 μg of infliximab. Six Dutch-belted pigmented rabbits received ocular alkali burn with NaOH. Immediately after the burn, subconjunctival implantation of anti-TNF-α DDS was performed in three rabbits while another three received sham DDS (without antibody). Rabbits were followed with photography for 3 months. After 3 months, the device was found to be well tolerated by the host and the eyes exhibited less corneal damage as compared to eyes implanted with a sham DDS without drug. The low dose treatment suppressed CD45 and TNF-α expression in the burned cornea and inhibited retinal ganglion cell apoptosis and optic nerve degeneration, as compared to the sham DDS treated eyes. Immunolocalization revealed drug penetration in the conjunctiva, cornea, iris, and choroid, with residual infliximab in the DDS 3 months after implantation. This reduced-risk biologic DDS improves corneal wound healing and provides retinal neuroprotection, and may be applicable not only to alkali burns but also to other inflammatory surgical procedures such as penetrating keratoplasty and keratoprosthesis implantation.

  8. Effect of biometric characteristics on biomechanical properties of the cornea in cataract patient

    Directory of Open Access Journals (Sweden)

    Xue-Fei Song

    2016-06-01

    Full Text Available AIM: To determine the impact of biometric characteristics on the biomechanical properties of the human cornea using the ocular response analyzer (ORA and standard comprehensive ophthalmic examinations before and after standard phacoemulsification. METHODS: This study comprised 54 eyes with cataract with significant lens opacification in stages I or II that underwent phacoemulsification (2.8 mm incision. Corneal hysteresis (CH, corneal resistance factor (CRF, Goldmann-correlated intraocular pressure (IOPg, and corneal-compensated intraocular pressure (IOPcc were measured by ORA preoperatively and at 1mo postoperatively. Biometric characteristics were derived from corneal topography [TMS-5, anterior equivalent (EQTMS and cylindric (CYLTMS power], corneal tomography [Casia, anterior and posterior equivalent (EQaCASIC, EQpCASIA and cylindric (CYLaCASIA, CYLpCASIA power], keratometry [IOLMaster, anterior equivalent (EQIOL and cylindric (CYLIOL power] and autorefractor [anterior equivalent (EQAR]. Results from ORA were analyzed and correlated with those from all other examinations taken at the same time point. RESULTS: Preoperatively, CH correlated with EQpCASIA and CYLpCASIA only (P=0.001, P=0.002. Postoperatively, IOPg and IOPcc correlated with all equivalent powers (EQTMS, EQIOL, EQAR, EQaCASIA and EQpCASIA (P=0.001, P=0.007, P=0.001, P=0.015, P=0.03 for IOPg and P<0.001, P=0.003, P<0.001, P=0.009, P=0.014 for IOPcc. CH correlated postoperatively with EQaCASIA and EQpCASIC only (P=0.021, P=0.022. CONCLUSION: Biometric characteristics may significantly affect biomechanical properties of the cornea in terms of CH, IOPcc and IOPg before, but even more after cataract surgery.

  9. Biocompatibility of a fish scale-derived artificial cornea: Cytotoxicity, cellular adhesion and phenotype, and in vivo immunogenicity.

    Science.gov (United States)

    van Essen, T H; van Zijl, L; Possemiers, T; Mulder, A A; Zwart, S J; Chou, C-H; Lin, C C; Lai, H J; Luyten, G P M; Tassignon, M J; Zakaria, N; El Ghalbzouri, A; Jager, M J

    2016-03-01

    To determine whether a fish scale-derived collagen matrix (FSCM) meets the basic criteria to serve as an artificial cornea, as determined with in vitro and in vivo tests. Primary corneal epithelial and stromal cells were obtained from human donor corneas and used to examine the (in)direct cytotoxicity effects of the scaffold. Cytotoxicity was assessed by an MTT assay, while cellular proliferation, corneal cell phenotype and adhesion markers were assessed using an EdU-assay and immunofluorescence. For in vivo-testing, FSCMs were implanted subcutaneously in rats. Ologen(®) Collagen Matrices were used as controls. A second implant was implanted as an immunological challenge. The FSCM was implanted in a corneal pocket of seven New Zealand White rabbits, and compared to sham surgery. The FSCM was used as a scaffold to grow corneal epithelial and stromal cells, and displayed no cytotoxicity to these cells. Corneal epithelial cells displayed their normal phenotypical markers (CK3/12 and E-cadherin), as well as cell-matrix adhesion molecules: integrin-α6 and β4, laminin 332, and hemi-desmosomes. Corneal stromal cells similarly expressed adhesion molecules (integrin-α6 and β1). A subcutaneous implant of the FSCM in rats did not induce inflammation or sensitization; the response was comparable to the response against the Ologen(®) Collagen Matrix. Implantation of the FSCM in a corneal stromal pocket in rabbits led to a transparent cornea, healthy epithelium, and, on histology, hardly any infiltrating immune cells. The FSCM allows excellent cell growth, is not immunogenic and is well-tolerated in the cornea, and thus meets the basic criteria to serve as a scaffold to reconstitute the cornea. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Analysis of the Viscoelastic Properties of the Human Cornea Using Scheimpflug Imaging in Inflation Experiment of Eye Globes

    Science.gov (United States)

    Lombardo, Giuseppe; Serrao, Sebastiano; Rosati, Marianna; Lombardo, Marco

    2014-01-01

    Purpose To demonstrate a Scheimpflug-based imaging procedure for investigating the depth- and time-dependent strain response of the human cornea to inflation testing of whole eye globes. Methods Six specimens, three of which with intact corneal epithelium, were mounted in a customized apparatus within a humidity and temperature-monitored wet chamber. Each specimen was subjected to two mechanical tests in order to measure corneal strain resulting from application of cyclic (cyclic regimen) and constant (creep regimen) stress by changing the intra-ocular pressure (IOP) within physiological ranges (18–42 mmHg). Corneal shape changes were analyzed as a function of IOP and both corneal stress-strain curves and creep curves were generated. Results The procedure was highly accurate and repeatable. Upon cyclic stress application, a biomechanical corneal elasticity gradient was found in the front-back direction. The average Young's modulus of the anterior cornea ranged between 2.28±0.87 MPa and 3.30±0.90 MPa in specimens with and without intact epithelium (P = 0.05) respectively. The Young's modulus of the posterior cornea was on average 0.21±0.09 MPa and 0.17±0.06 MPa (P>0.05) respectively. The time-dependent strain response of the cornea to creep testing was quantified by fitting data to a modified Zener model for extracting both the relaxation time and compliance function. Conclusion Cyclic and creep mechanical tests are valuable for investigating the strain response of the intact human cornea within physiological IOP ranges, providing meaningful results that can be translated to clinic. The presence of epithelium influences the results of anterior corneal shape changes when monitoring deformation via Scheimpflug imaging in inflation experiments of whole eye globes. PMID:25397674

  11. Clinical and epidemiological aspects of cornea transplant patients of a reference hospital.

    Science.gov (United States)

    Cruz, Giovanna Karinny Pereira; Azevedo, Isabelle Campos de; Carvalho, Diana Paula de Souza Rego Pinto; Vitor, Allyne Fortes; Santos, Viviane Euzébia Pereira; Ferreira, Marcos Antonio

    2017-06-08

    clinically characterizing cornea transplant patients and their distribution according to indicated and post-operative conditions of cornea transplantation, as well as estimating the average waiting time. a cross-sectional, descriptive and analytical study performed for all cornea transplants performed at a reference service (n=258). Data were analyzed using Statistical Package for the Social Sciences, version 20.0. the main indicator for cornea transplant was keratoconus. The mean waiting time for the transplant was approximately 5 months and 3 weeks for elective transplants and 9 days for urgent cases. An association between the type of corneal disorder with gender, age, previous surgery, eye classification, glaucoma and anterior graft failure were found. keratoconus was the main indicator for cornea transplant. Factors such as age, previous corneal graft failure (retransplantation), glaucoma, cases of surgeries prior to cornea transplant (especially cataract surgery) may be related to the onset corneal endothelium disorders. caracterizar clínicamente los pacientes trasplantados y su distribución, con descripción de las condiciones indicadoras y posoperatorias de los trasplantes de córneas, así como estimar el tiempo promedio en la fila de espera. estudio epidemiológico, transversal, descriptivo y analítico, realizado con todos los trasplantes de córnea realizados en un servicio de referencia (n=258). Los datos fueron analizados con el software Statistical Package for the Social Sciences, versión 20.0. la principal condición indicadora para el trasplante de córnea fue el queratocono. El tiempo promedio en fila de espera para realización del trasplante fue de aproximadamente 5 meses y tres semanas, para trasplantes electivos y de 9 días para los casos de urgencia. Existió asociación entre el tipo de disturbio de la córnea con: sexo, intervalo etario, cirugía previa, clasificación del ojo, glaucoma y rechazo del injerto anterior. el queratocono fue

  12. Escala de Locus de controle ELCO/TELEBRÁS Scale of Locus of control - ELCO

    Directory of Open Access Journals (Sweden)

    Luiz Pasquali

    1998-01-01

    Full Text Available Com base na teoria de Rotter e Escala de Levenson foi elaborada uma escala de Locus de Controle Organizacional (ELCO, composta por 28 itens. A escala foi validada com uma amostra de 350 empregados do Sistema Telebrás. Verificou-se a presença dos 2 fatores previstos na teoria, a saber: internalidade e externalidade, aparecendo a escala de externalidade, com 18 itens, bem estruturada (alfa = 0.81 e a de internalidade, com 10 itens, deixando a desejar no que se refere à consistência interna (alfa = 0.66. Com os dados desta pesquisa foi feita também análise do Locus de Controle desses mesmos empregados. A constatação mais saliente foi a de que o nível de internalidade caiu com o aumento do nível escolar e o aumento da experiência profissional desses mesmos empregados. Estes resultados surpreendentes foram interpretados em termos da situação típica da empresa, que está passando por um período de transição, a saber: a passagem da condição de empresa estatal para empresa privada, o que seria motivo da perda de confiança dos empregados na própria competência, particularmente por parte daqueles com maior competência intelectual e maior experiência profissional. Fez-se igualmente reparos na qualidade psicométrica da escala e da própria teoria do Locus de controle, no sentido de que esta precisa ser melhor axiomatizada para possibilitar a elaboração de escalas mais precisas para a medida dos construtos que propõe.A scale with 28 items, the Organizational Locus of Control (ELCO, was built based on Rotter’s theory and Levenson’s scale. ELCO was validated on a sample of 350 employees of Telebrás, a governmental firm in Brazil. As foreseen from the theory, a principal-axis factoring showed the presence of the expected two factors, namely internal and external locus of control. The external locus of control factor, composed of 18 items, showed good internal consistency (alpha =.81 whereas the internal factor, with 10 items

  13. Cushing syndrome

    Science.gov (United States)

    Hypercortisolism; Cortisol excess; Glucocorticoid excess - Cushing syndrome ... The most common cause of Cushing syndrome is taking too much ... Cushing syndrome . Prednisone, dexamethasone, and prednisolone ...

  14. LEOPARD syndrome

    Science.gov (United States)

    Multiple lentigines syndrome; Noonan syndrome with multiple lentigines ... Genetics Home Reference -- ghr.nlm.nih.gov/condition/noonan-syndrome-with-multiple-lentigines National Organization for Rare Disorders -- ...

  15. Collagen organization in the chicken cornea and structural alterations in the retinopathy, globe enlarged (rge) phenotype--an X-ray diffraction study.

    Science.gov (United States)

    Boote, Craig; Hayes, Sally; Jones, Simon; Quantock, Andrew J; Hocking, Paul M; Inglehearn, Chris F; Ali, Manir; Meek, Keith M

    2008-01-01

    An investigation into the collagenous structure of the mature avian cornea is presented. Wide-angle X-ray diffraction is employed to assess collagen organization in 9-month-old chicken corneas. The central 2-4mm corneal region features a preponderance of fibrils directed along the superior-inferior and nasal-temporal orthogonal meridians. More peripherally the orientation of fibrils alters in favor of a predominantly tangential arrangement. The chicken cornea appears to be circumscribed by an annulus of fibrils that extends into the limbus. The natural arrangement of collagen in the chicken cornea is discussed in relation to corneal shape and the mechanical requirements of avian corneal accommodation. Equivalent data are also presented from age-matched blind chickens affected with the retinopathy, globe enlarged (rge) mutation, characterized by an abnormally thick and flat cornea. The data indicate considerable realignment and redistribution of collagen lamellae in the peripheral rge cornea. In contrast to normal chickens, no obvious tangential collagen alignment was evident in the periphery of rge corneas. In mammals, the presence of a limbal fibril annulus is believed to be important in corneal shape preservation. We postulate that corneal flattening in rge chickens may be related to biomechanical changes brought about by an alteration in collagen arrangement at the corneal periphery.

  16. The Naïve Murine Cornea as a Model System to Identify Novel Endogenous Regulators of Lymphangiogenesis: TRAIL and rtPA.

    Science.gov (United States)

    Regenfuß, Birgit; Dreisow, Marie-Luise; Hos, Deniz; Masli, Sharmila; Bock, Felix; Cursiefen, Claus

    2015-06-01

    In the murine cornea, which is an established model for analyzing pathologic lymphatic vessel growth, phenotypic heterogeneity of the endogenous lymphatic vessels in the limbus of the cornea was previously described. In this study, the cornea of BALB/c, C57BL/6, and FVB mice with different limbal lymphangiogenic phenotypes was analyzed to identify novel candidates potentially influencing lymphatic vessel growth. Pathway specific expression analysis of the cornea was performed to identify novel candidate genes. Corneal protein expression of the respective candidates was analyzed by fluorescent immunohistochemistry. The effect of the candidates on proliferation of human dermal lymphatic endothelial cells (HDLECs) was analyzed by BrdU proliferation ELISA. Thirteen genes were differentially regulated in corneas of mouse strains with more endogenous limbal lymphatic vessels (high-lymphangiogenic) (C57BL/6) compared to mouse strains with less endogenous limbal lymphatic vessels (low-lymphangiogenic) (BALB/c, FVB). Two candidates, Tumor necrosis factor (ligand) superfamily member 10 (Tnfsf10/Trail) and Plasminogen activator, tissue (Plat/tPA) were expressed in the cornea of BALB/c and C57BL/6 mice on the protein level. In vitro, Trail and recombinant tPA inhibited the proliferation of human dermal lymphatic endothelial cells. Molecular analysis of the naive cornea in mouse strains with different limbal lymphatic phenotypes is a valuable model to identify novel endogenous regulators of lymphangiogenesis.

  17. Health Locus of Control尺度開発の歴史(社会科学編)

    OpenAIRE

    吉田, 由美; Yumi, YOSHIDA; 千葉県立衛生短期大学(看護学); Chiba College of Health Science

    1994-01-01

    This article describes the origins history of Health Locus of Control scales. First, Rotter's social learing theory, which is the theoretical background of the Health Locus of Control construct, is outlined. The scale and research trends of Locus of Control concept, and those of Health Locus of Control concept which are based on Locus of Control, are then reviewed. Finally, Health Locus of Control is discussed with regard to the implications for health education.

  18. A comparison study of Riboflavin/UV-A and Rose-Bengal/Green light cross-linking of the rabbit corneas using optical coherence elastography

    Science.gov (United States)

    Li, Jiasong; Singh, Manmohan; Han, Zhaolong; Vantipalli, Srilatha; Liu, Chih-Hao; Wu, Chen; Raghunathan, Raksha; Kazemi, Tina; Twa, Michael D.; Larin, Kirill V.

    2016-03-01

    The biomechanical properties of the cornea are critical factors which determine its health and subsequent visual acuity. Keratoconus is a structural degeneration of the cornea which can diminish vision quality. Riboflavin/UV-A corneal collagen cross-linking (UV-CXL) is an emerging treatment that increases the stiffness of the cornea and improves its ability to resist further degeneration. While UV-CXL has shown great promise for effective therapy of the keratoconus, there are concerns associated with the UV irradiation, such as keratocyte cytotoxicity. Rose-bengal/green light corneal collagen cross-linking (RGX) has been proposed as an alternative to UV-CXL. Because of the high absorbance of the rose-bengal dye at green wavelengths, the treatment time is significantly shorter than with UV-CXL. Moreover, because green light is used in lieu of UV irradiation, there are no cytotoxic side-effects. In this study, noncontact optical coherence elastography (OCE) was used to compare the outcomes of UV-CXL and RGX treatment in rabbit cornea. Low-amplitude (micrometer scale) elastic waves were induced by a focused air-pulse loading system. The elastic wave propagation was then imaged by a phase-stabilized swept source OCE (PhS-SSOCE) system. The changes in the viscoelasticity of the corneas were quantified by a previously developed modified Rayleigh Lamb frequency model. The depth-resolved micro-scale phase-velocity distribution in the cornea was used to reveal the depth-wise heterogeneity before and after both cross-linking techniques. Our results show that UV-CXL and RGX increased the stiffness of the corneas by ~54% and ~5% while reducing the viscosity by ~42% and ~17%, respectively. The depth-wise phase velocities showed that UV-CXL affected the anterior ~1/3 of the corneas, while RGX only affected the anterior ~1/7 of the corneas.

  19. Novel micelle carriers for cyclosporin A topical ocular delivery: in vivo cornea penetration, ocular distribution and efficacy studies.

    Science.gov (United States)

    Di Tommaso, Claudia; Bourges, Jean-Louis; Valamanesh, Fatemeh; Trubitsyn, Gregory; Torriglia, Alicia; Jeanny, Jean-Claude; Behar-Cohen, Francine; Gurny, Robert; Möller, Michael

    2012-06-01

    Cornea transplantation is one of the most performed graft procedures worldwide with an impressive success rate of 90%. However, for "high-risk" patients with particular ocular diseases in addition to the required surgery, the success rate is drastically reduced to 50%. In these cases, cyclosporin A (CsA) is frequently used to prevent the cornea rejection by a systemic treatment with possible systemic side effects for the patients. To overcome these problems, it is a challenge to prepare well-tolerated topical CsA formulations. Normally high amounts of oils or surfactants are needed for the solubilization of the very hydrophobic CsA. Furthermore, it is in general difficult to obtain ocular therapeutic drug levels with topical instillations due to the corneal barriers that efficiently protect the intraocular structures from foreign substances thus also from drugs. The aim of this study was to investigate in vivo the effects of a novel CsA topical aqueous formulation. This formulation was based on nanosized polymeric micelles as drug carriers. An established rat model for the prevention of cornea graft rejection after a keratoplasty procedure was used. After instillation of the novel formulation with fluorescent labeled micelles, confocal analysis of flat-mounted corneas clearly showed that the nanosized carriers were able to penetrate into all corneal layers. The efficacy of a 0.5% CsA micelle formulation was tested and compared to a physiological saline solution and to a systemic administration of CsA. In our studies, the topical CsA treatment was carried out for 14 days, and the three parameters (a) cornea transparency, (b) edema, and (c) neovascularization were evaluated by clinical observation and scoring. Compared to the control group, the treated group showed a significant higher cornea transparency and significant lower edema after 7 and 13 days of the surgery. At the end point of the study, the neovascularization was reduced by 50% in the CsA-micelle treated

  20. Fanconi syndrome

    Science.gov (United States)

    De Toni-Fanconi syndrome ... Fanconi syndrome can be caused by faulty genes, or it may result later in life due to kidney damage. Sometimes the cause of Fanconi syndrome is unknown. Common causes of Fanconi syndrome in ...

  1. Duane Syndrome

    Science.gov (United States)

    ... Frequently Asked Questions Español Condiciones Chinese Conditions Duane Syndrome En Español Read in Chinese What is Duane Syndrome? Duane syndrome, also called Duane retraction syndrome (DRS), ...

  2. EL LOCUS DE DISTRIBUCION COMO COROLARIO DEL LOCUS DE CONTROL (THE LOCUS OF DISTRIBUTION AS A COROLLARY TO THE LOCUS OF CONTROL

    Directory of Open Access Journals (Sweden)

    Mayoral Luisa

    2009-08-01

    Full Text Available Resumen: Este es un artículo científico acerca del Locus de Distribución, surgido de un estudio realizado con una población de docentes y alumnos universitarios. Respecto de los primeros, se ha indagado acerca de las atribuciones que se realizaban en torno a las recompensas y sanciones, que ellos distribuían a sus alumnos.Respecto de los segundos, se ha buscado determinar la valoración que estos realizaban de sus profesores, en términos de aquellas atribuciones. Para ello, se utilizaron dos paradigmas clásicamente empleados para verificar la existencia de una norma: el paradigma de la autopresentación (docentes, y el paradigma de los j uicios (alumnos. La cuestión planteada fue determinar si en el caso de los comportamientos distributivos de refuerzos, las causas se atribuían a variables externas -en particular a los receptores de esos refuerzos- y si esas formas de atribución eran conocidas y valoradas o no, por los alumnos. De los resultados, surgió la confirmación de nuestra hipótesis de explicaciones externas en materia de comportamientos distributivos de sanciones en el ámbito de la docencia y la valoración positiva de estas atribuciones por los alumnos.Abstract:This one is a scientific article brings over of the Locus of Distribution, arisen from a study realized with a population of teachers and university pupils. Respect of the first ones, it has been investigated brings over of the attributions that were concerning around the reinforcements which they were distributing to pupils. Respect of the second ones, one has sought to determine the valuation that these realized of the teachers, in terms of those attributions. For it, two paradigms were in use classic used to check the existence of a norm: the paradigm of the auto-presentation (teachers, and the paradigm of the judgments (pupils The raised question was to determine if in case of the distributive behaviours of reinforcements, the reasons were assuming to external

  3. Relation of organizational citizenship behavior and locus of control.

    Science.gov (United States)

    Turnipseed, David L; Bacon, Calvin M

    2009-12-01

    The relation of organizational citizenship behavior and locus of control was assessed in a sample of 286 college students (52% men; M age = 24 yr.) who worked an average of 26 hr. per week. Measures were Spector's Work Locus of Control Scale and Podsakoff, et al.'s Organization Citizenship Behavior scale. Hierarchical multiple regressions indicated positive association of scores on work locus of control with scores on each of the four tested dimensions of organizational citizenship, as well as total organizational citizenship behavior.

  4. Association of microsatellite polymorphisms of the GPDS1 locus with normal tension glaucoma in the Japanese population

    Directory of Open Access Journals (Sweden)

    Kayo Nakamura

    2009-04-01

    Full Text Available Kayo Nakamura1*, Masao Ota2*, Akira Meguro1, et al1Department of Ophthalmology, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan; 2Departmentof Legal Medicine, Shinshu University School of Medicine, Matsumoto, Nagano, JapanBackground: To investigate whether the GPDS1 locus, a potential causative locus of pigment-dispersion syndrome, is associated with normal-tension glaucoma (NTG in Japanese patients. Materials and methods: We used polymerase chain reaction amplification with sequencespecific primers to analyze 20 polymorphic microsatellite markers in and around the GPDS1 locus with an automated DNA analyzer and automated fragment detection by fluorescent-based technology. The DNA samples used for these analyses were obtained from ethnicity- and gendermatched patients, including 141 Japanese patients with NTG and 101 healthy controls. Patients exhibiting a comparatively early onset were selected as this suggests that genetic factors may show stronger involvement.Results: One allele of D7S2462 exhibited a frequency that was significantly decreased in NTG cases compared to controls (P = 0.0013, Pc = 0.019, OR = 0.48, 95% CI = 0.30–0.75. Alleles at another six microsatellite loci were positively or negatively associated with NTG, but these associations did not retain statistical significance after Bonferroni correction (P < 0.05, Pc > 0.05.Conclusion: Our study showed a significant association between the GPDS1 locus and NTG, suggesting that there may be some genetic risk factor(s in the development of NTG.Keywords: microsatellite, normal tension glaucoma, glaucoma-related pigment dispersion syndrome, GPDS1, DPP6

  5. Autism, fever, epigenetics and the locus coeruleus.

    Science.gov (United States)

    Mehler, Mark F; Purpura, Dominick P

    2009-03-01

    Some children with autism spectrum disorders (ASD) exhibit improved behaviors and enhanced communication during febrile episodes. We hypothesize that febrigenesis and the behavioral-state changes associated with fever in autism depend upon selective normalization of key components of a functionally impaired locus coeruleus-noradrenergic (LC-NA) system. We posit that autistic behaviors result from developmental dysregulation of LC-NA system specification and neural network deployment and modulation linked to the core behavioral features of autism. Fever transiently restores the modulatory functions of the LC-NA system and ameliorates autistic behaviors. Fever-induced reversibility of autism suggests preserved functional integrity of widespread neural networks subserving the LC-NA system and specifically the subsystems involved in mediating the cognitive and behavioral repertoires compromised in ASD. Alterations of complex gene-environmental interactions and associated epigenetic mechanisms during seminal developmental critical periods are viewed as instrumental in LC-NA dysregulation as emphasized by the timing and severity of prenatal maternal stressors on autism prevalence. Our hypothesis has implications for a rational approach to further interrogate the interdisciplinary etiology of ASD and for designing novel biological detection systems and therapeutic agents that target the LC-NA system's diverse network of pre- and postsynaptic receptors, intracellular signaling pathways and dynamic epigenetic remodeling processes involved in their regulation and functional plasticity.

  6. Hamartomatous polyposis syndromes

    DEFF Research Database (Denmark)

    Jelsig, Anne Marie; Qvist, Niels; Brusgaard, Klaus

    2014-01-01

    Hamartomatous Polyposis Syndromes (HPS) are genetic syndromes, which include Peutz-Jeghers syndrome, Juvenile polyposis syndrome, PTEN hamartoma tumour syndrome (Cowden Syndrom, Bannayan-Riley-Ruvalcaba and Proteus Syndrome) as well as hereditary mixed polyposis syndrome. Other syndromes such as ......Hamartomatous Polyposis Syndromes (HPS) are genetic syndromes, which include Peutz-Jeghers syndrome, Juvenile polyposis syndrome, PTEN hamartoma tumour syndrome (Cowden Syndrom, Bannayan-Riley-Ruvalcaba and Proteus Syndrome) as well as hereditary mixed polyposis syndrome. Other syndromes...

  7. Social influence of a religious hero: the late Cardinal Stephen Kim Sou-hwan's effect on cornea donation and volunteerism.

    Science.gov (United States)

    Bae, Hyuhn-Suhck; Brown, William J; Kang, Seok

    2011-01-01

    This study examined the mediated influence of a celebrated religious hero in South Korea, Cardinal Stephen Kim, through two forms of involvement--parasocial interaction and identification--on intention toward cornea donation and volunteerism, and it investigated how the news media diffused of his death. A structural equation modeling analysis with a Web-based voluntary survey of more than 1,200 people in South Korea revealed a multistep social influence process, beginning with parasocial interaction with Cardinal Kim, leading to identification with him, which predicted intention toward cornea donation and volunteerism. Additional investigations found that news of Cardinal Kim's death diffused rapidly through media and interpersonal communication. Results of this study demonstrate that religious leaders who achieve a celebrity hero status can prompt public discussion of important issues rather quickly through extensive media coverage, enabling them to promote prosocial behavior and positively affect public health.

  8. Oxidative Stress to the Cornea, Changes in Corneal Optical Properties, and Advances in Treatment of Corneal Oxidative Injuries

    Directory of Open Access Journals (Sweden)

    Cestmir Cejka

    2015-01-01

    Full Text Available Oxidative stress is involved in many ocular diseases and injuries. The imbalance between oxidants and antioxidants in favour of oxidants (oxidative stress leads to the damage and may be highly involved in ocular aging processes. The anterior eye segment and mainly the cornea are directly exposed to noxae of external environment, such as air pollution, radiation, cigarette smoke, vapors or gases from household cleaning products, chemical burns from splashes of industrial chemicals, and danger from potential oxidative damage evoked by them. Oxidative stress may initiate or develop ocular injury resulting in decreased visual acuity or even vision loss. The role of oxidative stress in the pathogenesis of ocular diseases with particular attention to oxidative stress in the cornea and changes in corneal optical properties are discussed. Advances in the treatment of corneal oxidative injuries or diseases are shown.

  9. Moorfields technique of donor cornea mounting for femtosecond-assisted keratoplasty: use of viscoelastic in the artificial anterior chamber.

    Science.gov (United States)

    Iovieno, Alfonso; Chowdhury, Vivek; Stevens, Julian D; Maurino, Vincenzo

    2012-07-01

    Appropriate mounting and cutting of the donor sclero-corneal cap is often cumbersome during femtosecond laser-assisted keratoplasty. The authors describe a technique for donor cornea femtosecond laser cutting using ophthalmic viscoelastic devices. The donor sclero-corneal cap is mounted on the artificial anterior chamber using a dispersive ophthalmic viscoelastic device instead of saline solution. The chances of artificial anterior chamber pressure loss, inadequate applanation, and fluid leaks are consistently reduced with the use of dispersive ophthalmic viscoelastic devices. The speed of donor femtosecond laser cutting is increased. The viscosity and elasticity of dispersive ophthalmic viscoelastic devices greatly assist the procedure with regard to ease of applanation, corneal endothelium protection, and decreased distortion of the applanated cornea. Copyright 2012, SLACK Incorporated.

  10. Multidimensional profiles of health locus of control in Hispanic Americans.

    Science.gov (United States)

    Champagne, Brian R; Fox, Rina S; Mills, Sarah D; Sadler, Georgia Robins; Malcarne, Vanessa L

    2016-10-01

    Latent profile analysis identified health locus of control profiles among 436 Hispanic Americans who completed the Multidimensional Health Locus of Control scales. Results revealed four profiles: Internally Oriented-Weak, -Moderate, -Strong, and Externally Oriented. The profile groups were compared on sociocultural and demographic characteristics, health beliefs and behaviors, and physical and mental health outcomes. The Internally Oriented-Strong group had less cancer fatalism, religiosity, and equity health attributions, and more alcohol consumption than the other three groups; the Externally Oriented group had stronger equity health attributions and less alcohol consumption. Deriving multidimensional health locus of control profiles through latent profile analysis allows examination of the relationships of health locus of control subtypes to health variables. © The Author(s) 2015.

  11. 240 INFLUENCES OF PEER RELATIONS AND LOCUS OF ...

    African Journals Online (AJOL)

    Financial recklessness is a behavior that has far reaching negative .... between consumer financial knowledge, income and locus of control on financial ... Their interactions with their peers increased their internal motivations and thus helped.

  12. Emotional intelligence and locus of control of adult patients with ...

    African Journals Online (AJOL)

    2011-03-15

    Mar 15, 2011 ... Keywords: breast cancer, treatment, positive psychology, emotional intelligence, locus of control ... branches are organised in a hierarchy with perception of ..... Asian. Development Bank Knowledge Solutions [serial online].

  13. Genetic Linkage Analysis of the DFNB21 Locus in Autosomal Recessive Hearing Loss in Large Families from Khuzestan Province

    Directory of Open Access Journals (Sweden)

    Mahtab Khosrofar

    2017-06-01

    Full Text Available Abstract Background: Hearing loss (HL is the most common congenital defect in humans. One or two in thousand newborn babies have prelingual hearing loss. Autosomal recessive non-syndromic hearing loss (ARNSHL is the most common form of hereditary deafness. Hearing loss is more common in the developing countries which is due to genetic and environmental (cultural -health factors reasons. HL has a wide range of clinical demonstrations including: congenital or late onset, conductive or sensory-neural, syndromic or non-syndromic hearing loss. The goal of this project is to determine the portion of the DFNB21 (TECTA in ARNSHL in families with negative GJB2 gene in Khuzestan province. Materials and Methods: We studied 21 families with ARNSHL with at least 4 patients and negative for GJB2 mutations from Khuzestan province. Genetic linkage analysis was performed using STR markers linked to DFNB21 locus. Results: Following genetic linkage analysis and haplotyping, out of 21 families with ARNSHL, one family showed linkage to the DFNB21 (TECTA locus. Conclusion: The results of this project confirm other studies in Iran and give insight into the most common loci causing ARNSHL in Iran which could be helpful in research and clinic.

  14. Cornea and anterior eye assessment with placido-disc keratoscopy, slit scanning evaluation topography and scheimpflug imaging tomography.

    Science.gov (United States)

    Martin, Raul

    2018-03-01

    Current corneal assessment technologies make the process of corneal evaluation extremely fast and simple and several devices and technologies allow to explore and to manage patients. The purpose of this special issue is to present and also to update in the evaluation of cornea and ocular surface and this second part, reviews a description of the corneal topography and tomography techniques, providing updated information of the clinical recommendations of these techniques in eye care practice. Placido-based topographers started an exciting anterior corneal surface analysis that allows the development of current corneal tomographers that provide a full three-dimensional reconstruction of the cornea including elevation, curvature, and pachymetry data of anterior and posterior corneal surfaces. Although, there is not an accepted reference standard technology for corneal topography description and it is not possible to determine which device produces the most accurate topographic measurements, placido-based topographers are a valuable technology to be used in primary eye care and corneal tomograhers expanding the possibilities to explore cornea and anterior eye facilitating diagnosis and follow-up in several situations, raising patient follow-up, and improving the knowledge regarding to the corneal anatomy. Main disadvantages of placido-based topographers include the absence of information about the posterior corneal surface and limited corneal surface coverage without data from the para-central and/or peripheral corneal surface. However, corneal tomographers show repeatable anterior and posterior corneal surfaces measurements, providing full corneal thickness data improving cornea, and anterior surface assessment. However, differences between devices suggest that they are not interchangeable in clinical practice.

  15. Collection, processing and testing of bone, corneas, umbilical cord blood and haematopoietic stem cells by European Blood Alliance members

    DEFF Research Database (Denmark)

    Närhi, M; Natri, O; Desbois, I

    2013-01-01

    A questionnaire study was carried out in collaboration with the European Blood Alliance (EBA) Tissues and Cells (T&C) working group. The aim was to assess the level of involvement and commonality of processes on the procurement, testing and storage of bone, corneas, umbilical cord blood (UCB......) and haematopoietic stem cells (HSC) in order to identify different practices and to explore whether recommendations can be made for harmonization....

  16. LOCUS OF CONTROL AND JOB SATISFACTION: PSU EMPLOYEES

    Directory of Open Access Journals (Sweden)

    Lakshman Vijayashree

    2011-11-01

    Full Text Available Previous research studies have demonstrated that internal/external locus of control impacts jobsatisfaction. The present study thus aims to analyze type of locus of control and its relation with jobsatisfaction. The study will be of great help for organization to understand and know what type oflocus of control their employees has and how it has an impact on job satisfaction.The objectives of this study were: 1- To identify the type of Locus of Control (i.e. Internal orExternal present in Public Sector Units (PSU in Bangalore and 2- To analyze the impact of differenttype of Locus of Control on job satisfaction of PSU Employees. Further hypothesis was also set tocheck the relationship between locus of control and job satisfaction. In addition, the relationshipbetween different demographic factors was also examined. The tool used for this study was LocoInventory. The concept of locus of control by Levenson (1972 was used to develop Loco Inventory(Locus of Control in Organization Inventory. The survey used a questionnaire, which had thirty fivestatements which highlights the factors that determine the locus of control and job satisfaction levelof the employees. The Ratio, ANOVA, and Correlation analysis were used as statistical techniquesfor analysis.The results indicate that there is a positive correlation between internal locus of control and jobsatisfaction as well as between External (other locus of control and job satisfaction. And in case ofExternal (Chance locus of control and job satisfaction there exists partial positive correlation. As perthis study Job satisfaction level among the employees is also good as the mean is 17, which is closerto maximum scale value of 25. As per ANOVA table there is a significant variance betweeninternality and age as well as between externality (chance and age. There is no significantrelationship between internality and demographic factors like gender and education. There is nosignificant relationship between

  17. The relationship between locus of control and career advancement

    OpenAIRE

    2014-01-01

    M.Com. (Industrial Psychology) The objective which career of this study advancement is was to investigate the extent to contingent on the personality construct locus of control. In order to achieve this, empirical research was conducted in a South African organisation. A survey questionnaire measuring career advancement and locus of control was completed by 152 subjects. The hypothesis which was formulated was that people with higher rates of career advancement would be more internal and t...

  18. Analysis of the ABCA4 genomic locus in Stargardt disease

    DEFF Research Database (Denmark)

    Zernant, Jana; Xie, Yajing Angela; Ayuso, Carmen

    2014-01-01

    excluded since they were not conserved in non-human primates, were frequent in African populations and, therefore, represented ancestral, and not disease-associated, variants. The sequence variability in the ABCA4 locus is extensive and the non-coding sequences do not harbor frequent mutations in STGD...... patients of European-American descent. Defining disease-associated alleles in the ABCA4 locus requires exceptionally well characterized large cohorts and extensive analyses by a combination of various approaches....

  19. Science Study For A Low Cost Upper Atmosphere Sounder (LOCUS)

    Science.gov (United States)

    Gerber, D.; Swinyard, B. M.; Ellison, B. N.; Siddans, R.; Kerridge, B. J.; Plane, J. M. C.; Feng, W.

    2013-12-01

    We present the findings of an initial science study to define the spectral bands for the proposed Mesosphere / Lower Thermosphere (MLT) sounder LOCUS. The LOCUS mission (Fig 1) uses disruptive technologies to make key MLT species detectable globally by satellite remote sensing for the first time. This presentation summarises the technological and scientific foundation on which the current 4-band Terahertz (THz) and sub- millimetre wave (SMW) instrument configuration was conceived.

  20. Mapping the x-linked lymphoproliferative syndrome

    International Nuclear Information System (INIS)

    Skare, J.C.; Milunsky, A.; Byron, K.S.; Sullivan, J.L.

    1987-01-01

    The X-linked lymphoproliferative syndrome is triggered by Epstein-Barr virus infection and results in fatal mononucleosis, immunodeficiency, and lymphoproliferative disorders. This study shows that the mutation responsible for X-linked lymphoproliferative syndrome is genetically linked to a restriction fragment length polymorphism detected with the DXS42 probe (from Xq24-q27). The most likely recombination frequency between the loci is 4%, and the associated logarithm of the odds is 5.26. Haplotype analysis using flanking restriction fragment length polymorphism markers indicates that the locus for X-linked lymphoproliferative syndrome is distal to probe DXS42 but proximal to probe DXS99 (from Xq26-q27). It is now possible to predict which members of a family with X-linked lymphoproliferative syndrome are carrier females and to diagnose the syndrome prenatally

  1. Mapping the x-linked lymphoproliferative syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Skare, J.C.; Milunsky, A.; Byron, K.S.; Sullivan, J.L.

    1987-04-01

    The X-linked lymphoproliferative syndrome is triggered by Epstein-Barr virus infection and results in fatal mononucleosis, immunodeficiency, and lymphoproliferative disorders. This study shows that the mutation responsible for X-linked lymphoproliferative syndrome is genetically linked to a restriction fragment length polymorphism detected with the DXS42 probe (from Xq24-q27). The most likely recombination frequency between the loci is 4%, and the associated logarithm of the odds is 5.26. Haplotype analysis using flanking restriction fragment length polymorphism markers indicates that the locus for X-linked lymphoproliferative syndrome is distal to probe DXS42 but proximal to probe DXS99 (from Xq26-q27). It is now possible to predict which members of a family with X-linked lymphoproliferative syndrome are carrier females and to diagnose the syndrome prenatally.

  2. Effect of In Vitro Transcorneal Approach of Aceclofenac Eye Drops through Excised Goat, Sheep, and Buffalo Corneas

    Directory of Open Access Journals (Sweden)

    Vivek Dave

    2015-01-01

    Full Text Available The current study involves the evaluation of factors that influence the transcorneal permeation of aqueous drops of aceclofenac ophthalmic formulation through freshly excised goat, sheep, and buffalo corneas. Aceclofenac formulation with different concentrations 0.1–0.5% (w/v and with different pH and different preservatives, was taken into account. The amount of drug permeated from different formulations was estimated using an Franz diffusion cell. A linear increase in drug permeation was observed with increase in pH (5.5 to 7.4. The apparent permeability coefficient was found to be maximum 15.01±0.45 on goat cornea and maximum transport of aceclofenac was observed at physiological pH of tears (i.e., 7. The results advocate that aceclofenac 0.5% (w/v ophthalmic solution (pH 7.0 containing BAK (0.01% provides maximum in vitro ocular permeability through goat, sheep, and buffalo corneas.

  3. Donor cornea procurement: six-year review of the role of the eye bank in South Australia.

    Science.gov (United States)

    Williams, K A; White, M A; Badenoch, P R; Wedding, T R; Alfrich, S J; Sawyer, M A; Noack, L M; Johnstone, E W; Zilm, G; Coster, D J

    1990-02-01

    The Lions Eye Bank of South Australia was established six years ago and has collected corneas from 790 donors. The consent rate is currently 82% of requests made. Two-thirds of donors have been male, with mean donor age/year varying from 54 to 64 years (range two to 93 years). Cardiovascular and respiratory diseases, trauma and haemorrhage account for 80% of all donor deaths. Mean death to enucleation time is five hours. Corneas assessed as being of excellent or very good quality are released preferentially from the bank; those with central endothelial cell counts of less than 1500 cells/mm2 are discarded. Fewer than 1% of donors have returned a positive result for HIV or hepatitis B. Of the 1580 corneas collected by the bank, 863 (55%) have been used for transplantation with a primary non-function rate of 0.46%. The evolving policies, logistics of operation and methodologies employed by the bank are described in detail.

  4. Novel method to avoid the open-sky condition in penetrating keratoplasty: covered cornea technique.

    Science.gov (United States)

    Arslan, Osman S; Unal, Mustafa; Arici, Ceyhun; Cicik, Erdoğan; Mangan, Serhat; Atalay, Eray

    2014-09-01

    The aim of this study was to present a novel technique to avoid the open-sky condition in pediatric and adult penetrating keratoplasty (PK). Seventy-two eyes of 65 infants and children and 44 eyes of 44 adult patients were operated on using this technique. After trephining the recipient cornea up to a depth of 50% to 70%, the anterior chamber was entered at 1 point. Then, only a 2 clock hour segment of the recipient button was incised, and this segment was sutured to the recipient rim with a single tight suture. The procedure was repeated until the entire recipient button was excised and resutured. The donor corneal button was sutured to the recipient corneal rim. The sutures between the recipient button and the rim were then cut off, and the recipient button was drawn out. None of the patients operated on with this technique developed complications related to the open-sky condition. Visual acuities, graft failure rates, and endothelial cell loss were comparable with the findings of studies performed for conventional PK. The technique described avoids the open-sky condition during the entire PK procedure. Endothelial cell loss rates are acceptable.

  5. Isolation and characterization of soluble sulfated polysaccharide from the red seaweed Glucaric cornea

    International Nuclear Information System (INIS)

    Melo, Marcia R.S.; Freitas, Ana L.P.; Feitosa, Judith P.A.; Paula, Regina C.M. de

    2001-01-01

    The composition, structure and rheological properties of soluble sulphated polysaccharide Glucaric cornea from Brazilian red seaweeds were investigated. The main components of polysaccharide were 3,6-anhydrogalactose (24.7%) and galactose (64.6%). In addition, minor components as 6-O-methyl-galactose (8.5%), glucose (1.5%), xylose (0.7%) and sulfated groups (4.8%) were detected. Comparison between sulphates content determined by Ft-IR spectroscopy and micro elemental analysis was made. Data from 13 C NMR and FT-IR provided evidence of sulphation in C-4 and C-6 of galactose. No gelation with 1.5, 2.0 and 3.0 % (w/v) aqueous solution was observed, even cooled up to 4 deg C. GPC indicated two majors polysaccharide fractions of M pk 7.4 x 10 4 and 1.8 x 10 4 g/mol and a minor fraction of M pk 2.1 x 10 6 g/mol. (author)

  6. Experimental investigations of the late effects of ionizing radiation on the cornea, 1

    International Nuclear Information System (INIS)

    Oinaka, Matsuyoshi

    1980-01-01

    Late effects of 60 Co gamma-irradiation (3,000 - 750 rad, single exposure, dose rate 45 rad/min.) on the rabbits cornea were investigated histopathologically. In 3,000 rad exposed series, superficial keratitis was seen at 5 weeks and stromal clouding, consisting of slight cell infiltration and edema, appeared at 7 weeks after irradiation. Light microscopically, loosening and flattening of the epithelial cells at 5 weeks, and only one layer of the epithelial cells remained at 7 weeks. Electron microscopically, degeneration of the corneal epithelium was seen at 5 weeks. These changes are probably due to irreversible mitosis inhibition. In 2,500 rad exposed series, superficial keratitis appeared at 5 weeks, but stromal clouding was not seen during the whole course. By light and electron microscopic examination, loosening and enlargement of the basal cells were observed, and modification of the superficial cells to non-polygonal shape was seen at 7 weeks. Degenerative findings of the epithelium were not seen. These changes are probably due to transient mitosis inhibition. The corneal endothelium was intact during the whole course in this series. Transient swelling and disordered arrangement of the basal cells in 1,500 rad exposed series and slight swelling of the basal cells in 750 rad exposed ones were seen at 5 weeks. Swelling and disordered arrangement of the corneal epithelium in less than 3,000 rad exposed groups were reversible. (author)

  7. Frozen cultured sheets of epidermal keratinocytes in reepithelialization and repair of the cornea after photorefractive keratectomy.

    Science.gov (United States)

    Castro-Muñozledo, Federico; Ozorno-Zarate, Jorge; Naranjo-Tackman, Ramon; Kuri-Harcuch, Walid

    2002-09-01

    To determine whether frozen cultured sheets of human allogeneic epidermal keratinocytes (CEAK) improved wound repair after experimental corneal ablation by photorefractive keratectomy (PRK). Hospital "Luis Sanchez Bulnes" de la Asociación para Evitar la Ceguera en Mexico, I.A.P, and Department of Cell Biology, CINVESTAV-IPN, Mexico City, Mexico. Transepithelial PRK was performed in the right eye of male albino rabbits to obtain a 112 microm deep and 6.0 mm diameter ablation zone. In 17 eyes, the ablations were covered with frozen CEAK; in 11 eyes, the ablations were covered with a disposable contact lens without the cultured sheets; and in the control group (13 eyes), the ablations were not covered. Subepithelial fibrosis and reepithelialization of the ablated zone were evaluated in serial paraffin-embedded tissue sections from all wounds. Treatment with CEAK reduced fibroblast proliferation and the inflammatory response beneath the ablated zone and produced better organization of the newly formed epithelium by eliminating significant hyperplasia or discontinuities in the periodic acid Shiff-stained basement membrane. It also led to accelerated reepithelialization. The use of frozen CEAK as a biologically active wound dressing improved tissue repair at 1 month in corneas ablated by transepithelial PRK in the male albino rabbit model. Treatment with CEAK could improve the outcome of PRK in humans.

  8. Precut cornea for Descemet's stripping endothelial keratoplasty: experience at a single eye bank.

    Science.gov (United States)

    Mohamed, Ashik; Chaurasia, Sunita; Chandragiri, Venkataswamy; Kandhibanda, Srinivas; Gunnam, Srinivas; Garg, Prashant

    2017-06-01

    The aim of the study is to describe the experience with precut facility for endothelial keratoplasty at a single eye bank affiliated to a tertiary eye care center in India. Data on precut tissues from Nov 2012 to Dec 2014 were retrospectively reviewed from the electronic database of the eye bank of a tertiary eye care center in South India. Donor characteristic data including donor age, precut and postcut endothelial cell density (ECD), recipient age, and thickness of graft were collected. The number of precuts increased from 42 in 2012 (Nov and Dec) and 422 in 2013 to 584 in 2014. Of the total of 1048 precuts, seven (0.67 %) were miscut and could not be utilized for transplants. The donor age ranged from 2 to 89 years. A mean change of 43.6 ± 325.2 cells/mm 2 in ECD was noted after cut, proportional increase in mean being 1.9 %. The change in ECD after cut was negatively correlated with ECD before cut. The recipient age ranged from 1 to 89 years. The median thickness of donor lenticule after cut was 148 µm (interquartile range 131-166 µm). Analysis of precut donor corneas from a single eye bank shows that the ECD of the processed tissues was excellent for transplantation. The tissue wastage in the hands of eye bank personal was minimal.

  9. INTACS before or after laser in situ keratomileusis: correction of thin corneas with moderately high myopia.

    Science.gov (United States)

    Ito, Mitsutoshi; Arai, Hiroyuki; Fukumoto, Teruki; Toda, Ikuko; Tsubota, Kazuo

    2004-01-01

    Intrastromal corneal ring segments (INTACS Micro-Thin Prescription Inserts by Addition Technologies, Fremont, Calif) were inserted as a combined surgery with laser in situ keratomileusis (LASIK) in six eyes with thin corneas to correct moderately high myopia. INTACS were implanted before LASIK (INTACS-LASIK) in three eyes and after LASIK (LASIK-INTACS) in three eyes. Mean preoperative manifest spherical equivalent refraction was -7.88 diopters. Mean follow-up was 306 days. No intraoperative complications occurred. The LASIK-INTACS eyes were slightly more overcorrected than the INTACS-LASIK eyes because of the enhanced performance of INTACS in the thinned corneal tissue. Induced astigmatism by INTACS per se was less in the LASIK-INTACS eyes than in the INTACS-LASIK eyes. At last examination, uncorrected visual acuity was better than 20/25 in all eyes. Best spectacle-corrected visual acuity was within 1 line of the preoperative value in all eyes. Both methods resulted in significant improvement in visual acuity and refraction. Based on our limited experience, however, LASIK followed by INTACS is preferred for reasons of safety, convenience, and lower induced cylinder.

  10. Development of a microfabricated artificial limbus with micropockets for cell delivery to the cornea

    International Nuclear Information System (INIS)

    Ortega, Ílida; Deshpande, Pallavi; Gill, Andrew A; MacNeil, Sheila; Claeyssens, Frederik

    2013-01-01

    The aim of this study was to develop a synthetic alternative to the human corneal limbus for use initially as an ex vivo model in which to study corneal stem cell function within a niche environment and ultimately to develop an implantable limbus for future clinical use. Microstereolithography was used for the fabrication of polyethylene glycol diacrylate (PEGDA) based rings on a macroscopic (1.2 cm) scale containing unique microfeatures (pockets) which were then modified with fibronectin to promote cell adhesion. These rings were designed to mimic the limbal area of the eye containing structures of the approximate size and shape of the stem cell microenvironments found in the palisades of Vogt. The attachment of rabbit limbal fibroblasts and rabbit limbal epithelial cells to the PEGDA rings was increased by pretreating the microfabricated structures with biotinylated fibronectin. Cell outgrowth from fibronectin coated microfabricated structures was 50% greater than from rings without structures or fibronectin coating. The cell loaded rings were then placed on an ex vivo wounded cornea model and the outgrowth of cells to form a multilayered epithelium was observed. We suggest this is a new approach to investigating limbal stem cells niches and the first steps towards a new approach for corneal regeneration. (paper)

  11. Descemet's stripping-automated endothelial keratoplasty for symptomatic thioridazine deposits in the cornea

    Directory of Open Access Journals (Sweden)

    Masoumeh Mohebbi

    2017-01-01

    Full Text Available The aim of this study was to use Descemet's Stripping-automated Endothelial Keratoplasty (DSAEK as a novel treatment to remove thioridazine corneal deposits. A 53-year-old female presented with a 3-month history of visual loss and glare. She had been taking thioridazine (100 mg/day for 1 year for a psychiatric disorder. Dense yellowish-brown deposits had developed in the posterior stroma. Thioridazine was discontinued, and she was switched to fluoxetine. One year after discontinuation of thioridazine, her symptoms and signs did not resolve. Standard DSAEK was performed on her left eye. Two weeks after DSAEK, an anterior subcapsular cataract was detected in the same eye. Phacoemulsification and intraocular lens implantation were performed after 3 months. The left cornea became completely clear after DSAEK, and the patient's best-corrected visual acuity improved from 20/40 to 20/20 at 1 month after cataract surgery. All-visual symptoms such as glare and halos improved postoperatively. We suggest that DSAEK can be used as a novel treatment to reduce vision problems caused by thioridazine-induced corneal deposits.

  12. Preparation of pre-cut corneas from fresh donated whole globes for Descemet's stripping automated keratoplasty: 3-year results at the Central Eye Bank of Iran.

    Science.gov (United States)

    Kanavi, Mozhgan Rezaei; Javadi, Mohammad Ali; Javadi, Fatemeh; Chamani, Tahereh

    2014-09-01

    To describe the technique and the results of the preparation of pre-cut corneas for Descemet's stripping automated endothelial keratoplasty (DSAEK) during a 3-year period at the Central Eye Bank of Iran (CEBI). The method of preparation of pre-cut corneas from donated whole globes at the CEBI is described and the frequency and percentage of pre-cut corneas prepared for DSAEK, between April 2009 and March 2012, are specified. Moreover, post-operative reports are reviewed for any complaints about using pre-cut tissues for DSAEK. Out of the 1,518 donated whole globes appropriate for DSAEK, 1,478 (97.4 %) pre-cut corneas were successfully prepared. The method of preparation failed in 40 (2.6 %) cases. Based on the eye bank post-operative reports, thickness of pre-cut tissues for DSAEK was deemed unacceptable in only 6 (0.4 %) cases prior to surgery; five of these were too thick and one was too thin. Preparation of pre-cut corneas, for DSAEK from donated whole globes, in the CEBI is a safe and easy method, with very good preservation of endothelial cells after the preparation of the pre-cut corneas and reduced risks from corneal manipulation.

  13. Fixation probability in a two-locus intersexual selection model.

    Science.gov (United States)

    Durand, Guillermo; Lessard, Sabin

    2016-06-01

    We study a two-locus model of intersexual selection in a finite haploid population reproducing according to a discrete-time Moran model with a trait locus expressed in males and a preference locus expressed in females. We show that the probability of ultimate fixation of a single mutant allele for a male ornament introduced at random at the trait locus given any initial frequency state at the preference locus is increased by weak intersexual selection and recombination, weak or strong. Moreover, this probability exceeds the initial frequency of the mutant allele even in the case of a costly male ornament if intersexual selection is not too weak. On the other hand, the probability of ultimate fixation of a single mutant allele for a female preference towards a male ornament introduced at random at the preference locus is increased by weak intersexual selection and weak recombination if the female preference is not costly, and is strong enough in the case of a costly male ornament. The analysis relies on an extension of the ancestral recombination-selection graph for samples of haplotypes to take into account events of intersexual selection, while the symbolic calculation of the fixation probabilities is made possible in a reasonable time by an optimizing algorithm. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Two-locus linkage analysis in multiple sclerosis (MS)

    Energy Technology Data Exchange (ETDEWEB)

    Tienari, P.J. (National Public Health Institute, Helsinki (Finland) Univ. of Helsinki (Finland)); Terwilliger, J.D.; Ott, J. (Columbia Univ., New York (United States)); Palo, J. (Univ. of Helsinki (Finland)); Peltonen, L. (National Public Health Institute, Helsinki (Finland))

    1994-01-15

    One of the major challenges in genetic linkage analyses is the study of complex diseases. The authors demonstrate here the use of two-locus linkage analysis in multiple sclerosis (MS), a multifactorial disease with a complex mode of inheritance. In a set of Finnish multiplex families, they have previously found evidence for linkage between MS susceptibility and two independent loci, the myelin basic protein gene (MBP) on chromosome 18 and the HLA complex on chromosome 6. This set of families provides a unique opportunity to perform linkage analysis conditional on two loci contributing to the disease. In the two-trait-locus/two-marker-locus analysis, the presence of another disease locus is parametrized and the analysis more appropriately treats information from the unaffected family member than single-disease-locus analysis. As exemplified here in MS, the two-locus analysis can be a powerful method for investigating susceptibility loci in complex traits, best suited for analysis of specific candidate genes, or for situations in which preliminary evidence for linkage already exists or is suggested. 41 refs., 6 tabs.

  15. [Health locus of control of patients in disease management programmes].

    Science.gov (United States)

    Schnee, M; Grikscheit, F

    2013-06-01

    Health locus of control beliefs plays a major role in improving self-management skills of the chronically ill - a main goal in disease management programmes (DMP). This study aims at characterising participants in disease management regarding their health locus of control. Data are based on 4 cross-sectional postal surveys between spring and autumn of 2006 and 2007 within the Health Care Monitor of the Bertelsmann Foundation. Among the 6 285 respondents, 1 266 are chronically ill and not enrolled in a DMP and 327 are participating in a DMP. A high internal locus of control (HLC) occurs significantly less often in DMP patients than in normal chronically ill patients (and healthy people) controlling for age, gender and social class. With increasing age, a high internal locus of control is also significantly less likely. When comparing healthy people, the chronically ill and the DMP participants a social gradient of a high internal locus of control belief can be observed. The weaker internal and higher doctor-related external locus of control of DMP participants should be carefully observed by the physician when trying to strengthen the patients' self-management skills. Evaluators of DMP should take into account the different baselines of DMP patients and relevant control groups and incorporate these differences into the evaluation. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Neurolinguistic programming training, trait anxiety, and locus of control.

    Science.gov (United States)

    Konefal, J; Duncan, R C; Reese, M A

    1992-06-01

    Training in the neurolinguistic programming techniques of shifting perceptual position, visual-kinesthetic dissociation, timelines, and change-history, all based on experiential cognitive processing of remembered events, leads to an increased awareness of behavioral contingencies and a more sensitive recognition of environmental cues which could serve to lower trait anxiety and increase the sense of internal control. This study reports on within-person and between-group changes in trait anxiety and locus of control as measured on the Spielberger State-Trait Anxiety Inventory and Wallston, Wallston, and DeVallis' Multiple Health Locus of Control immediately following a 21-day residential training in neurolinguistic programming. Significant with-in-person decreases in trait-anxiety scores and increases in internal locus of control scores were observed as predicted. Chance and powerful other locus of control scores were unchanged. Significant differences were noted on trait anxiety and locus of control scores between European and U.S. participants, although change scores were similar for the two groups. These findings are consistent with the hypothesis that this training may lower trait-anxiety scores and increase internal locus of control scores. A matched control group was not available, and follow-up was unfortunately not possible.

  17. DNA modification study of major depressive disorder: beyond locus-by-locus comparisons.

    Science.gov (United States)

    Oh, Gabriel; Wang, Sun-Chong; Pal, Mrinal; Chen, Zheng Fei; Khare, Tarang; Tochigi, Mamoru; Ng, Catherine; Yang, Yeqing A; Kwan, Andrew; Kaminsky, Zachary A; Mill, Jonathan; Gunasinghe, Cerisse; Tackett, Jennifer L; Gottesman, Irving I; Willemsen, Gonneke; de Geus, Eco J C; Vink, Jacqueline M; Slagboom, P Eline; Wray, Naomi R; Heath, Andrew C; Montgomery, Grant W; Turecki, Gustavo; Martin, Nicholas G; Boomsma, Dorret I; McGuffin, Peter; Kustra, Rafal; Petronis, Art

    2015-02-01

    Major depressive disorder (MDD) exhibits numerous clinical and molecular features that are consistent with putative epigenetic misregulation. Despite growing interest in epigenetic studies of psychiatric diseases, the methodologies guiding such studies have not been well defined. We performed DNA modification analysis in white blood cells from monozygotic twins discordant for MDD, in brain prefrontal cortex, and germline (sperm) samples from affected individuals and control subjects (total N = 304) using 8.1K CpG island microarrays and fine mapping. In addition to the traditional locus-by-locus comparisons, we explored the potential of new analytical approaches in epigenomic studies. In the microarray experiment, we detected a number of nominally significant DNA modification differences in MDD and validated selected targets using bisulfite pyrosequencing. Some MDD epigenetic changes, however, overlapped across brain, blood, and sperm more often than expected by chance. We also demonstrated that stratification for disease severity and age may increase the statistical power of epimutation detection. Finally, a series of new analytical approaches, such as DNA modification networks and machine-learning algorithms using binary and quantitative depression phenotypes, provided additional insights on the epigenetic contributions to MDD. Mapping epigenetic differences in MDD (and other psychiatric diseases) is a complex task. However, combining traditional and innovative analytical strategies may lead to identification of disease-specific etiopathogenic epimutations. Copyright © 2015 Society of Biological Psychiatry. All rights reserved.

  18. A comparison of interocular differences in patients with pigment dispersion syndrome.

    Science.gov (United States)

    Yip, Leonard W; Sothornwit, Nisa; Berkowitz, Jonathan; Mikelberg, Frederick S

    2009-01-01

    Pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG) are characterized by loss of iris pigment because of reverse pupillary block. The loss of iris pigment is manifested as transillumination defects. Differences in ocular anatomy have been found between subjects with PDS and controls. Our study aims to see if differences in interocular anatomic features are also related to differences in the quantity of transillumination defects between eyes. This is an observational case series of 30 eyes of 15 subjects with PDS/PG in at least 1 eye. Patients underwent refraction, exophthalmometry, corneal and anterior chamber analysis by Pentacam, biometry, A-scan, ultrasound biomicroscopy, and anterior segment digital photography. The Pentacam mean central radii of the posterior corneal surface (cornea back Rm), vertical central radius of curvature of the posterior corneal surface (cornea back Rv), and keratometric power deviation (influence of the posterior surface of the cornea on refractive power) were statistically different between eyes with greater pigment loss and eyes with lesser pigment loss. Eyes with greater pigment loss had a larger back radius of corneal curvature and a correspondingly numerically smaller keratometric power deviation. Other measurements of ocular anatomy were not statistically significant. A flatter curvature of the posterior corneal surface of the eye is associated with increased pigment loss in PDS and PG. The authors postulate that this could result in a difference in the biomechanical properties of the cornea, increased deformation with blinking, and a pumping action resulting in the reverse pupil block of PDS.

  19. A short-term study of corneal collagen cross-linking with hypo-osmolar riboflavin solution in keratoconic corneas

    Directory of Open Access Journals (Sweden)

    Shao-Feng Gu

    2015-02-01

    Full Text Available AIM: To report the 3mo outcomes of collagen cross-linking (CXL with a hypo-osmolar riboflavin in thin corneas with the thinnest thickness less than 400 μm without epithelium. METHODS: Eight eyes in 6 patients with age 26.2±4.8y were included in the study. All patients underwent CXL using a hypo-osmolar riboflavin solution after its de-epithelization. Best corrected visual acuity, manifest refraction, the thinnest corneal thickness, and endothelial cell density were evaluated before and 3mo after the procedure. RESULTS: The mean thinnest thickness of the cornea was 408.5±29.0 μm before treatment and reduced to 369.8±24.8 μm after the removal of epithelium. With the application of the hypo-osmolar riboflavin solution, the thickness increased to 445.0±26.5 μm before CXL and recover to 412.5±22.7 μm at 3mo after treatment, P=0.659. Before surgery, the mean K-value of the apex of the keratoconus corneas was 57.6±4.0 diopters, and slightly decreased (54.7±4.9 diopters after surgery (P=0.085. Mean best-corrected visual acuity was 0.55±0.23 logarithm of the minimal angle of resolution, and increased to 0.53±0.26 logarithm after surgery (P=0.879. The endothelial cell density was 2706.4±201.6 cells/mm2 before treatment, and slightly decreased (2641.2±218.2 cells/mm2 at last fellow up (P=0.002. CONCLUSION: Corneal collagen cross-linking with a hypo-osmolar riboflavin in thin corneas seems to be a promising treatment. Further study should be done to evaluate the safety and efficiency of CXL in thin corneas for the long-term.

  20. Fissured and geographic tongue in Williams-Beuren syndrome

    Directory of Open Access Journals (Sweden)

    Neeta Sharma

    2014-01-01

    Full Text Available Williams-Beuren Syndrome (WBS is a rare, most often sporadic, genetic disease caused by a chromosomal microdeletion at locus 7q11.23 involving 28 genes. It is characterized by congenital heart defects, neonatal hypercalcemia, skeletal and renal abnormalities, cognitive disorder, social personality disorder, and dysmorphic facies. A number of clinical findings has been reported, but none of the studies evaluated this syndrome considering oral cavity. We here report a fissured and geographic tongue in association with WBS.

  1. The Increasing Complexity of the Oncofetal H19 Gene Locus: Functional Dissection and Therapeutic Intervention

    Directory of Open Access Journals (Sweden)

    Abraham Hochberg

    2013-02-01

    Full Text Available The field of the long non-coding RNA (lncRNA is advancing rapidly. Currently, it is one of the most popular fields in the biological and medical sciences. It is becoming increasingly obvious that the majority of the human transcriptome has little or no-protein coding capacity. Historically, H19 was the first imprinted non-coding RNA (ncRNA transcript identified, and the H19/IGF2 locus has served as a paradigm for the study of genomic imprinting since its discovery. In recent years, we have extensively investigated the expression of the H19 gene in a number of human cancers and explored the role of H19 RNA in tumor development. Here, we discuss recently published data from our group and others that provide further support for a central role of H19 RNA in the process of tumorigenesis. Furthermore, we focus on major transcriptional modulators of the H19 gene and discuss them in the context of the tumor-promoting activity of the H19 RNA. Based on the pivotal role of the H19 gene in human cancers, we have developed a DNA-based therapeutic approach for the treatment of cancers that have upregulated levels of H19 expression. This approach uses a diphtheria toxin A (DTA protein expressed under the regulation of the H19 promoter to treat tumors with significant expression of H19 RNA. In this review, we discuss the treatment of four cancer indications in human subjects using this approach, which is currently under development. This represents perhaps one of the very few examples of an existing DNA-based therapy centered on an lncRNA system. Apart from cancer, H19 expression has been reported also in other conditions, syndromes and diseases, where deregulated imprinting at the H19 locus was obvious in some cases and will be summarized below. Moreover, the H19 locus proved to be much more complicated than initially thought. It houses a genomic sequence that can transcribe, yielding various transcriptional outputs, both in sense and antisense directions. The

  2. Prader-Willi syndrome in South African patients clinical and ...

    African Journals Online (AJOL)

    Prader-Willi syndrome in. South African patients clinical and molecular diagnosis. A L Christianson, 0 L Viljoen, W S Winship,. M de la Rey, E J van Rensburg. Study objective. ... This probe detects a parent-of-origin-specific methylation imprint at locus ... These studies were undertaken in the Molecular Genetic. Laboratory of ...

  3. Clinical and molecular phenotype of Aicardi-Goutieres syndrome

    NARCIS (Netherlands)

    Rice, Gillian; Patrick, Teresa; Parmar, Rekha; Taylor, Claire F.; Aeby, Alec; Aicardi, Jean; Artuch, Rafael; Montalto, Simon Attard; Bacino, Carlos A.; Barroso, Bruno; Baxter, Peter; Benko, Willam S.; Bergmann, Carsten; Bertini, Enrico; Biancheri, Roberta; Blair, Edward M.; Blau, Nenad; Bonthron, David T.; Briggs, Tracy; Brueton, Louise A.; Brunner, Han G.; Burke, Christopher J.; Carr, Ian M.; Carvalho, Daniel R.; Chandler, Kate E.; Christen, Hans-Jurgen; Corry, Peter C.; Cowan, Frances M.; Cox, Helen; D'Arrigo, Stefano; Dean, John; de Laet, Corinne; de Praeter, Claudine; Dery, Catherine; Ferrie, Colin D.; Flintoff, Kim; Frints, Suzanna G. M.; Garcia-Cazorla, Angels; Gener, Blanca; Goizet, Cyril; Goutieres, Francoise; Green, Andrew J.; Guet, Agnes; Hamel, Ben C. J.; Hayward, Bruce E.; Heiberg, Arvid; Hennekam, Raoul C.; Husson, Marie; Jackson, Andrew P.; Jayatunga, Rasieka; Jiang, Yong-Hui; Kant, Sarina G.; Kao, Amy; King, Mary D.; Kingston, Helen M.; Klepper, Joerg; van der Knaap, Marjo S.; Kornberg, Andrew J.; Kotzot, Dieter; Kratzer, Wilfried; Lacombe, Didier; Lagae, Lieven; Landrieu, Pierre Georges; Lanzi, Giovanni; Leitch, Andrea; Lim, Ming J.; Livingston, John H.; Lourenco, Charles M.; Lyall, E. G. Hermione; Lynch, Sally A.; Lyons, Michael J.; Marom, Daphna; McClure, John P.; McWilliam, Robert; Melancon, Serge B.; Mewasingh, Leena D.; Moutard, Marie-Laure; Nischal, Ken K.; Ostergaard, John R.; Prendiville, Julie; Rasmussen, Magnhild; Rogers, R. Curtis; Roland, Dominique; Rosser, Elisabeth M.; Rostasy, Kevin; Roubertie, Agathe; Sanchis, Amparo; Schiffmann, Raphael; Scholl-Burgi, Sabine; Seal, Sunita; Shalev, Stavit A.; Corcoles, C. Sierra; Sinha, Gyan P.; Soler, Doriette; Spiegel, Ronen; Stephenson, John B. P.; Tacke, Uta; Tan, Tiong Yang; Till, Marianne; Tolmie, John L.; Tomlin, Pam; Vagnarelli, Federica; Valente, Enza Maria; van Coster, Rudy N. A.; van der Aa, Nathalie; Vanderver, Adeline; Vles, Johannes S. H.; Voit, Thomas; Wassmer, Evangeline; Weschke, Bernhard; Whiteford, Margo L.; Willemsen, Michel A. A.; Zankl, Andreas; Zuberi, Sameer M.; Orcesi, Simona; Fazzi, Elisa; Lebon, Pierre; Crow, Yanick J.

    2007-01-01

    Aicardi-Goutieres syndrome (AGS) is a genetic encephalopathy whose clinical features mimic those of acquired in utero viral infection. AGS exhibits locus heterogeneity, with mutations identified in genes encoding the 3'-->5' exonuclease TREX1 and the three subunits of the RNASEH2 endonuclease

  4. A case of Silver–Russell syndrome (SRS): multiple pituitary ...

    Indian Academy of Sciences (India)

    Hypomethylation of the imprinting control region 1 (ICR1) at the IGF2/H19 locus on 11p15 is linked to Silver–Russell syndrome .... lowing criteria have to be met: low birth weight, short stature ..... school-aged children and adolescents. Bull.

  5. Expression analyses of the genes harbored by the type 2 diabetes and pediatric BMI associated locus on 10q23

    Directory of Open Access Journals (Sweden)

    Zhao Jianhua

    2012-09-01

    Full Text Available Abstract Background There is evidence that one of the key type 2 diabetes (T2D loci identified by GWAS exerts its influence early on in life through its impact on pediatric BMI. This locus on 10q23 harbors three genes, encoding hematopoietically expressed homeobox (HHEX, insulin-degrading enzyme (IDE and kinesin family member 11 (KIF11, respectively. Methods We analyzed the impact of adipogeneis on the mRNA and protein expression levels of these genes in the human adipocyte Simpson-Golabi-Behmel syndrome (SGBS cell line in order to investigate which could be the culprit gene(s in this region of linkage disequilibrium. Results Following activation of differentiation with a PPARγ ligand, we observed ~20% decrease in IDE, ~40% decrease in HHEX and in excess of 80% decrease in KIF11 mRNA levels when comparing the adipocyte and pre-adipocyte states. We also observed decreases in KIF11 and IDE protein levels, but conversely we observed a dramatic increase in HHEX protein levels. Subsequent time course experiments revealed some marked changes in expression as early as three hours after activation of differentiation. Conclusion Our data suggest that the expression of all three genes at this locus are impacted during SGBS adipogenesis and provides insights in to the possible mechanisms of how the genes at this 10q23 locus could influence both adipocyte differentiation and susceptibility to T2D through insulin resistance.

  6. Orphan Hereditary Syndromes in the Practice of Pediatric Endocrinologist

    Directory of Open Access Journals (Sweden)

    M.O. Ryznychuk

    2015-05-01

    Above-mentioned syndromes are caused by different gene mutations, namely Perlman syndrome — by homozygous or heterozygous mutation in DIS3L2 gene on the chromosome 2q37, Proteus syndrome — mutation in AKT1 gene on chromosome 14q32.3, Sotos syndrome 1 is caused by heterozygous mutation in NSD1 gene in the 5q35 region, Sotos syndrome 2 — by heterozygous mutation in NFIX gene on chromosome 19p13.3. Berardinelli syndrome, which is divided into four types, has four different mutations, namely: type 1 is caused by mutations in AGPAT2 gene in locus 9q34, type 2 — in BSCα2gene in locus 11q13, type 3 — by mutations in CAV1 gene (locus 7q31, type 4 — by mutation in PTRF gene located on the chromosome 17.

  7. Effects of androgen replacement therapy on cornea and tear function in men with idiopathic hypogonadotropic hypogonadism.

    Science.gov (United States)

    Gokce, Gokcen; Hurmeric, Volkan; Mumcuoglu, Tarkan; Ozge, Gokhan; Basaran, Yalcin; Unal, Hilmi Umut; Bolu, Erol; Mutlu, Fatih Mehmet

    2015-05-01

    Idiopathic hypogonadotropic hypogonadism (IHH) is an endocrine disorder defined with the presence of typical clinical signs and symptoms plus laboratory confirmation of serum testosterone (T) levels lower than 300 ng/dl. Androgen replacement therapy (ART) is the first-step treatment of male IHH. To date, no clinical trial, which investigates the changes on corneal structure and tear function, of systemic ART in men have been published. The objective of this study was to investigate the effects of ART on cornea and tear function in patients with IHH. This prospective, interventional study was conducted at the Gulhane Military Medical Academy, Ankara, Turkey, a tertiary referral military hospital. Thirty-four eyes of 17 men with IHH patients were evaluated with Schirmer I test, ultrasound pachymeter, applanation tonometer and confocal microscopy. A Testosterone compound (Sustanon® 250 mg) was administered by intramuscular injection in the course of a 3-week period to induce puberty, and human chorionic gonadotropin (Pregnyl® 5000 IU) was administered twice weekly for 3 months to induce fertility. The patients were re-evaluated at the third month of the treatment. Main Outcome Measures were Schirmer score, central corneal thickness (CCT), intraocular pressure (IOP), endothelial cell density, coefficient of variation and cell shape. Schirmer scores showed similar results after the treatment compared to pre-treatment levels (p = 0.14). There was no statistically significant difference in CCT and IOP compared to baseline data (p = 0.96, p = 0.73, respectively), and no significant differences were found in corneal endothelial cell density, percentage of cell size variability or hexagonality (p = 0.83, p = 0.58, p = 0.64, respectively). This is the first study that investigates the effects of ART on corneal structure and tear function in men. ART seems to have no short-term effects on corneal structure and tear function. Further publications of larger, long-term and

  8. Ocular manifestations of Marfan syndrome in children and adolescents.

    Science.gov (United States)

    Salchow, Daniel J; Gehle, Petra

    2018-03-01

    To study ocular manifestations of Marfan syndrome in children and adolescents. Retrospective comparative cohort study on consecutive patients up to age 17 years, presenting to the interdisciplinary Marfan clinic of Charité-University Medicine Berlin over a period of 4 years. A total of 52 Marfan syndrome patients and 73 controls were enrolled. In Marfan syndrome eyes, the cornea was flatter (mean keratometry, 40.86 ± 2.13 vs 42.55 ± 1.55 diopters in control eyes, p Marfan syndrome eyes (537.35 ± 40.64 vs 552.95 ± 38.57 μm, p = 0.007) and Marfan syndrome eyes were more myopic than control eyes (spherical equivalent, -2.77 ± 4.77 vs -0.64 ± 1.92 diopters, p Marfan syndrome eyes. Iris transillumination defects were more common in Marfan syndrome eyes (19.6% vs 4.3% in control eyes, odds ratio for Marfan syndrome in the presence of iris transillumination defects = 7.2). Ectopia lentis was only found in Marfan syndrome eyes (25 Marfan syndrome patients, 49% with available data, bilateral in 68%). Iris transillumination defects and ectopia lentis are characteristic ocular findings in children and adolescents with Marfan syndrome. Myopia is more common and corneal curvature, central corneal thickness, and visual acuity are reduced in Marfan syndrome eyes. Children with Marfan syndrome need regular comprehensive eye examinations to identify potential complications.

  9. Marfan Syndrome

    Science.gov (United States)

    Marfan syndrome is a disorder that affects connective tissue. Connective tissues are proteins that support skin, bones, blood vessels, ... A problem with the fibrillin gene causes Marfan syndrome. Marfan syndrome can be mild to severe, and ...

  10. Aarskog syndrome

    Science.gov (United States)

    Aarskog disease; Aarskog-Scott syndrome; AAS; Faciodigitogenital syndrome; Gaciogenital dysplasia ... Aarskog syndrome is a genetic disorder that is linked to the X chromosome. It affects mainly males, but females ...

  11. Williams syndrome

    Science.gov (United States)

    Williams-Beuren syndrome ... Williams syndrome is caused by not having a copy of several genes. It may be passed down in families. ... history of the condition. However, people with Williams syndrome have a 50% chance of passing the disorder ...

  12. Cushing's Syndrome

    OpenAIRE

    宗, 友厚; 伊藤, 勇; 諏訪, 哲也; 武田, 純; MUNE, Tomoatsu

    2003-01-01

    Sixteen cases of verified Cushing's syndrome, and twelve cases of probable Cushing's syndrome were reviewed and data on them were compared with various reports on Cushing's syndrome in the literature.

  13. Tourette syndrome

    Science.gov (United States)

    Gilles de la Tourette syndrome; Tic disorders - Tourette syndrome ... Tourette syndrome is named for Georges Gilles de la Tourette, who first described this disorder in 1885. The disorder is likely passed down through families. ...

  14. Mutation at the Human D1S80 Minisatellite Locus

    Directory of Open Access Journals (Sweden)

    Kuppareddi Balamurugan

    2012-01-01

    Full Text Available Little is known about the general biology of minisatellites. The purpose of this study is to examine repeat mutations from the D1S80 minisatellite locus by sequence analysis to elucidate the mutational process at this locus. This is a highly polymorphic minisatellite locus, located in the subtelomeric region of chromosome 1. We have analyzed 90,000 human germline transmission events and found seven (7 mutations at this locus. The D1S80 alleles of the parentage trio, the child, mother, and the alleged father were sequenced and the origin of the mutation was determined. Using American Association of Blood Banks (AABB guidelines, we found a male mutation rate of 1.04×10-4 and a female mutation rate of 5.18×10-5 with an overall mutation rate of approximately 7.77×10-5. Also, in this study, we found that the identified mutations are in close proximity to the center of the repeat array rather than at the ends of the repeat array. Several studies have examined the mutational mechanisms of the minisatellites according to infinite allele model (IAM and the one-step stepwise mutation model (SMM. In this study, we found that this locus fits into the one-step mutation model (SMM mechanism in six out of seven instances similar to STR loci.

  15. Inferring Demographic History Using Two-Locus Statistics.

    Science.gov (United States)

    Ragsdale, Aaron P; Gutenkunst, Ryan N

    2017-06-01

    Population demographic history may be learned from contemporary genetic variation data. Methods based on aggregating the statistics of many single loci into an allele frequency spectrum (AFS) have proven powerful, but such methods ignore potentially informative patterns of linkage disequilibrium (LD) between neighboring loci. To leverage such patterns, we developed a composite-likelihood framework for inferring demographic history from aggregated statistics of pairs of loci. Using this framework, we show that two-locus statistics are more sensitive to demographic history than single-locus statistics such as the AFS. In particular, two-locus statistics escape the notorious confounding of depth and duration of a bottleneck, and they provide a means to estimate effective population size based on the recombination rather than mutation rate. We applied our approach to a Zambian population of Drosophila melanogaster Notably, using both single- and two-locus statistics, we inferred a substantially lower ancestral effective population size than previous works and did not infer a bottleneck history. Together, our results demonstrate the broad potential for two-locus statistics to enable powerful population genetic inference. Copyright © 2017 by the Genetics Society of America.

  16. Hepatorenal syndrome

    Science.gov (United States)

    ... 2016:chap 153. Nevah MI, Fallon MB. Hepatic encephalopathy, hepatorenal syndrome, hepatopulmonary syndrome, and other systemic complications of liver disease. In: Feldman M, Friedman LS, Brandt LJ, ...

  17. Genomic locus modulating corneal thickness in the mouse identifies POU6F2 as a potential risk of developing glaucoma.

    Directory of Open Access Journals (Sweden)

    Rebecca King

    2018-01-01

    Full Text Available Central corneal thickness (CCT is one of the most heritable ocular traits and it is also a phenotypic risk factor for primary open angle glaucoma (POAG. The present study uses the BXD Recombinant Inbred (RI strains to identify novel quantitative trait loci (QTLs modulating CCT in the mouse with the potential of identifying a molecular link between CCT and risk of developing POAG. The BXD RI strain set was used to define mammalian genomic loci modulating CCT, with a total of 818 corneas measured from 61 BXD RI strains (between 60-100 days of age. The mice were anesthetized and the eyes were positioned in front of the lens of the Phoenix Micron IV Image-Guided OCT system or the Bioptigen OCT system. CCT data for each strain was averaged and used to QTLs modulating this phenotype using the bioinformatics tools on GeneNetwork (www.genenetwork.org. The candidate genes and genomic loci identified in the mouse were then directly compared with the summary data from a human POAG genome wide association study (NEIGHBORHOOD to determine if any genomic elements modulating mouse CCT are also risk factors for POAG.This analysis revealed one significant QTL on Chr 13 and a suggestive QTL on Chr 7. The significant locus on Chr 13 (13 to 19 Mb was examined further to define candidate genes modulating this eye phenotype. For the Chr 13 QTL in the mouse, only one gene in the region (Pou6f2 contained nonsynonymous SNPs. Of these five nonsynonymous SNPs in Pou6f2, two resulted in changes in the amino acid proline which could result in altered secondary structure affecting protein function. The 7 Mb region under the mouse Chr 13 peak distributes over 2 chromosomes in the human: Chr 1 and Chr 7. These genomic loci were examined in the NEIGHBORHOOD database to determine if they are potential risk factors for human glaucoma identified using meta-data from human GWAS. The top 50 hits all resided within one gene (POU6F2, with the highest significance level of p = 10-6 for

  18. Locus-specific view of flax domestication history

    Science.gov (United States)

    Fu, Yong-Bi; Diederichsen, Axel; Allaby, Robin G

    2012-01-01

    Crop domestication has been inferred genetically from neutral markers and increasingly from specific domestication-associated loci. However, some crops are utilized for multiple purposes that may or may not be reflected in a single domestication-associated locus. One such example is cultivated flax (Linum usitatissimum L.), the earliest oil and fiber crop, for which domestication history remains poorly understood. Oil composition of cultivated flax and pale flax (L. bienne Mill.) indicates that the sad2 locus is a candidate domestication locus associated with increased unsaturated fatty acid production in cultivated flax. A phylogenetic analysis of the sad2 locus in 43 pale and 70 cultivated flax accessions established a complex domestication history for flax that has not been observed previously. The analysis supports an early, independent domestication of a primitive flax lineage, in which the loss of seed dispersal through capsular indehiscence was not established, but increased oil content was likely occurred. A subsequent flax domestication process occurred that probably involved multiple domestications and includes lineages that contain oil, fiber, and winter varieties. In agreement with previous studies, oil rather than fiber varieties occupy basal phylogenetic positions. The data support multiple paths of flax domestication for oil-associated traits before selection of the other domestication-associated traits of seed dispersal loss and fiber production. The sad2 locus is less revealing about the origin of winter tolerance. In this case, a single domestication-associated locus is informative about the history of domesticated forms with the associated trait while partially informative on forms less associated with the trait. PMID:22408732

  19. T-style keratoprosthesis based on surface-modified poly (2-hydroxyethyl methacrylate) hydrogel for cornea repairs

    International Nuclear Information System (INIS)

    Xiang, Jun; Sun, Jianguo; Hong, Jiaxu; Wang, Wentao; Wei, Anji; Le, Qihua; Xu, Jianjiang

    2015-01-01

    Corneal disease is a common cause of blindness, and keratoplasty is considered as an effective treatment method. However, there is a severe shortage of donor corneas worldwide. This paper presents a novel T-style design of a keratoprosthesis and its preparation methods, in which a mechanically and structurally effective artificial cornea is made based on a poly(2-hydroxyethyl methacrylate) hydrogel. The porous skirt was modified with hyaluronic acid and cationized gelatin, and the bottom of the optical column was coated with poly(ethylene glycol). The physical properties of the T-style Kpro were analyzed using ultraviolet and visible spectrophotometry and electron scanning microscopy. The surface chemical properties were characterized using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface modification in the spongy skirt promoted cell adhesion and produced a firm bond between the corneal tissue and the implant device, while the surface modification in the optic column resisted cell adhesion and prevented retroprosthetic membrane formation. Through improved surgical techniques, the novel T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with the host environment. In vivo implantation experiments showed that the T-style keratoprosthesis is a promising cornea alternative for patients with severe limbal stem cell deficiency and corneal opacity. - Highlights: • T-style keratoprosthesis was designed and prepared based on a PHEMA hydrogel. • Selective surface modifications effectively regulated cells' selective adhesion. • T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with host tissues

  20. T-style keratoprosthesis based on surface-modified poly (2-hydroxyethyl methacrylate) hydrogel for cornea repairs

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Jun [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Sun, Jianguo [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); State Key Laboratory of Molecular Engineering of Polymers, Fudan University (China); Hong, Jiaxu [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Wang, Wentao [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Wei, Anji [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Le, Qihua [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Xu, Jianjiang, E-mail: jianjiang-xu@163.com [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China)

    2015-05-01

    Corneal disease is a common cause of blindness, and keratoplasty is considered as an effective treatment method. However, there is a severe shortage of donor corneas worldwide. This paper presents a novel T-style design of a keratoprosthesis and its preparation methods, in which a mechanically and structurally effective artificial cornea is made based on a poly(2-hydroxyethyl methacrylate) hydrogel. The porous skirt was modified with hyaluronic acid and cationized gelatin, and the bottom of the optical column was coated with poly(ethylene glycol). The physical properties of the T-style Kpro were analyzed using ultraviolet and visible spectrophotometry and electron scanning microscopy. The surface chemical properties were characterized using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface modification in the spongy skirt promoted cell adhesion and produced a firm bond between the corneal tissue and the implant device, while the surface modification in the optic column resisted cell adhesion and prevented retroprosthetic membrane formation. Through improved surgical techniques, the novel T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with the host environment. In vivo implantation experiments showed that the T-style keratoprosthesis is a promising cornea alternative for patients with severe limbal stem cell deficiency and corneal opacity. - Highlights: • T-style keratoprosthesis was designed and prepared based on a PHEMA hydrogel. • Selective surface modifications effectively regulated cells' selective adhesion. • T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with host tissues.

  1. Loss of the BMP antagonist, SMOC-1, causes Ophthalmo-acromelic (Waardenburg Anophthalmia) syndrome in humans and mice

    NARCIS (Netherlands)

    Rainger, J.; Beusekom, E. van; Ramsay, J.K.; McKie, L.; Al-Gazali, L.; Pallotta, R.; Saponari, A.; Branney, P.; Fisher, M.; Morrison, H.; Bicknell, L.; Gautier, P.; Perry, P.; Sokhi, K.; Sexton, D.; Bardakjian, T.M.; Schneider, A.S.; Elcioglu, N.; Ozkinay, F.; Koenig, R.; Megarbane, A.; Semerci, C.N.; Khan, A.; Zafar, S.; Hennekam, R.; Sousa, S.B.; Ramos, L.; Garavelli, L.; Furga, A.S.; Wischmeijer, A.; Jackson, I.J.; Gillessen-Kaesbach, G.; Brunner, H.G.; Wieczorek, D.; Bokhoven, J.H.L.M. van; FitzPatrick, D.R.

    2011-01-01

    Ophthalmo-acromelic syndrome (OAS), also known as Waardenburg Anophthalmia syndrome, is defined by the combination of eye malformations, most commonly bilateral anophthalmia, with post-axial oligosyndactyly. Homozygosity mapping and subsequent targeted mutation analysis of a locus on 14q24.2

  2. Loss of the BMP Antagonist, SMOC-1, Causes Ophthalmo-Acromelic (Waardenburg Anophthalmia) Syndrome in Humans and Mice

    NARCIS (Netherlands)

    Rainger, J.; van Beusekom, E.; Ramsay, J.K.; McKie, L.; Al-Gazali, L.; Pallotta, R.; Saponari, A.; Branney, P.; Fisher, M.; Morrison, H.; Bicknell, L.; Gautier, P.; Perry, P.; Sokhi, K.; Sexton, D.; Bardakjian, T.M.; Schneider, A.S.; Elcioglu, N.; Ozkinay, F.; Koenig, R.; Megarbane, A.; Semerci, C.N.; Khan, A.; Zafar, S.; Hennekam, R.; Sousa, S.B.; Ramos, L.; Garavelli, L.; Furga, A.S.; Wischmeijer, A.; Jackson, I.J.; Gillessen-Kaesbach, G.; Brunner, H.G.; Wieczorek, D; van Bokhoven, H.; Fitzpatrick, D.R.

    2011-01-01

    Ophthalmo-acromelic syndrome (OAS), also known as Waardenburg Anophthalmia syndrome, is defined by the combination of eye malformations, most commonly bilateral anophthalmia, with post-axial oligosyndactyly. Homozygosity mapping and subsequent targeted mutation analysis of a locus on 14q24.2

  3. [Observation and analysis on mutation of routine STR locus].

    Science.gov (United States)

    Li, Qiu-yang; Feng, Wei-jun; Yang, Qin-gen

    2005-05-01

    To observe and analyze the characteristic of mutation at STR locus. 27 mutant genes observed in 1211 paternity testing cases were checked by PAGE-silver stained and PowerPlex 16 System Kit and validated by sequencing. Mutant genes locate on 15 loci. The pattern of mutation was accord with stepwise mutation model. The mutation ratio of male-to-female was 8:1 and correlated to the age of father. Mutation rate is correlated to the geometric mean of the number of homogeneous repeats of locus. The higher the mean, the higher the mutation rate. These loci are not so appropriate for use in paternity testing.

  4. Microscopia confocal de la córnea en facoemulsificación Confocal microscopy of the cornea on phacoemulsification

    Directory of Open Access Journals (Sweden)

    Juan Raúl Hernández Silva

    2011-12-01

    Full Text Available Objetivo: Determinar los cambios estructurales de la córnea en la cirugía de catarata por facoemulsificación sin complicaciones. Métodos: Se realizó un estudio prospectivo de pacientes operados de catarata por facoemulsificación coaxial por la técnica de pre chop sin complicaciones. A estos se les realizó microscopia confocal de la córnea con el CONFOSCAN 4 (Nidek Technologies con el objetivo de 40x y adaptador Z-Ring. Se realizó el estudio en el preoperatorio y en el posoperatorio (a las 24 horas, después de una semana, de un mes y a los tres meses. Resultados: Se demostraron cambios estructurales en la córnea como células epiteliales con núcleos hiperreflectivos alargadas en ocasiones y áreas de hiperreflectividad anómala a las 24 horas del posoperatorio. Persistieron queratocitos activados y la disminución de la hiperreflectividad de la matriz extracelular que desapareció al mes. Conclusiones: Aunque por biomicroscopia no se observen alteraciones corneales en el posoperatorio de la cirugía de catarata por facoemulsificación, sí se pueden demostrar por microscopia confocal de la córnea. Estas variaciones no influyen en la recuperación visual óptima de los pacientes.Objective: To determine the structural changes in the cornea in the cataract surgery using phacoemulsification without complications. Methods: A prospective study of patients operated on from cataract using the coaxial phacoemulsification (Pre Chop technique without complications was carried out. These patients also underwent confocal microscopy of the cornea with Confoscan4 (Nidek Technologies with 40x target and Z - Ring adapter. The study was performed in the preoperative period and postoperative period for 24 hours, one week, one month and three months after surgery. Results: Structural changes were observed in the cornea such as epithelial cells with hypereflectivity nucleus, occasionally elongated, , areas of anomalous hypereflectivity 24 hours after

  5. Role of Mesenchymal Stem Cells on Cornea Wound Healing Induced by Acute Alkali Burn

    Science.gov (United States)

    Yao, Lin; Li, Zhan-rong; Su, Wen-ru; Li, Yong-ping; Lin, Miao-li; Zhang, Wen-xin; Liu, Yi; Wan, Qian; Liang, Dan

    2012-01-01

    The aim of this study was to investigate the effects of subconjunctivally administered mesenchymal stem cells (MSCs) on corneal wound healing in the acute stage of an alkali burn. A corneal alkali burn model was generated by placing a piece of 3-mm diameter filter paper soaked in NaOH on the right eye of 48 Sprague-Dawley female rats. 24 rats were administered a subconjunctival injection of a suspension of 2×106 MSCs in 0.1 ml phosphate-buffered saline (PBS) on day 0 and day 3 after the corneal alkali burn. The other 24 rats were administered a subconjunctival injection of an equal amount of PBS as a control. Deficiencies of the corneal epithelium and the area of corneal neovascularization (CNV) were evaluated on days 3 and 7 after the corneal alkali burn. Infiltrated CD68+ cells were detected by immunofluorescence staining. The mRNA expression levels of macrophage inflammatory protein-1 alpha (MIP-1α), tumor necrosis factor-alpha (TNF-α), monocyte chemotactic protein-1 (MCP-1) and vascular endothelial growth factor (VEGF) were analyzed using real-time polymerase chain reaction (real-time PCR). In addition, VEGF protein levels were analyzed using an enzyme-linked immunosorbent assay (ELISA). MSCs significantly enhanced the recovery of the corneal epithelium and decreased the CNV area compared with the control group. On day 7, the quantity of infiltrated CD68+ cells was significantly lower in the MSC group and the mRNA levels of MIP-1α, TNF-α, and VEGF and the protein levels of VEGF were also down-regulated. However, the expression of MCP-1 was not different between the two groups. Our results suggest that subconjunctival injection of MSCs significantly accelerates corneal wound healing, attenuates inflammation and reduces CNV in alkaline-burned corneas; these effects were found to be related to a reduction of infiltrated CD68+ cells and the down-regulation of MIP-1α, TNF-α and VEGF. PMID:22363499

  6. The effect of hypergravity on the lens, cornea and tail regeneration in Urodela

    Science.gov (United States)

    Grigoryan, E. N.; Dvorochkin, N.; Poplinskaya, V. A.; Yousuf, R.; Radugina, E. A.; Almeida, E. A.

    2017-09-01

    In previous experiments onboard Russian Bion/Foton satellites it was found that exposure to microgravity causes changes in eye lens regeneration of Urodela. The changes included higher rate of regeneration, increased cell proliferation in lens anlage, and synchronization of lens restoration. Similar changes were observed regarding tail regeneration. Recently, investigations were performed to find out whether exposure to hypergravity could also alter lens, cornea and tail regeneration in the newt P. waltl. Nine days prior to exposure the left lens was surgically removed through corneal incision and distal 1/3 of the tail was amputated, thus initiating regeneration. The experimental animals were allowed to recover for 9 days at 1 g and then exposed to 2 g for 12 days in an 8 ft diameter centrifuge at NASA Ames Research Center. The experimental animals were divided into 1 g controls, 2 g centrifugation animals, basal controls, and aquarium controls. Lens and corneal regeneration appeared to be inhibited in 2 g group compared to 1 g animals. In all 1 g controls, lens regeneration reached stages VII-IX in a synchronous fashion and corneal regeneration was nearly complete. In the 2 g newts, neural retinal detachment from the pigmented epithelium was seen in most operated eyes. It was also observed in the non-operated (right) eyes of the animals exposed to 2 g. The level of retinal detachment varied and could have been caused by hypergravity-induced high intraocular pressure. Regeneration (when it could be assessed) proceeded asynchronously, reaching stages from II to IX. Corneal restoration was also noticeably delayed and corneal morphology changed. Cell proliferation was measured using BrdU; the results were not comparable to the 1 g data because of retinal detachment. Previous investigations demonstrated that lens regeneration was controlled by the neural retina; therefore, lower regeneration rate at 2 g was, at least in part, associated with retinal detachment. FGF2

  7. Heterotic trait locus (HTL) mapping identifies intra-locus interactions that underlie reproductive hybrid vigor in Sorghum bicolor.

    Science.gov (United States)

    Ben-Israel, Imri; Kilian, Benjamin; Nida, Habte; Fridman, Eyal

    2012-01-01

    Identifying intra-locus interactions underlying heterotic variation among whole-genome hybrids is a key to understanding mechanisms of heterosis and exploiting it for crop and livestock improvement. In this study, we present the development and first use of the heterotic trait locus (HTL) mapping approach to associate specific intra-locus interactions with an overdominant heterotic mode of inheritance in a diallel population using Sorghum bicolor as the model. This method combines the advantages of ample genetic diversity and the possibility of studying non-additive inheritance. Furthermore, this design enables dissecting the latter to identify specific intra-locus interactions. We identified three HTLs (3.5% of loci tested) with synergistic intra-locus effects on overdominant grain yield heterosis in 2 years of field trials. These loci account for 19.0% of the heterotic variation, including a significant interaction found between two of them. Moreover, analysis of one of these loci (hDPW4.1) in a consecutive F2 population confirmed a significant 21% increase in grain yield of heterozygous vs. homozygous plants in this locus. Notably, two of the three HTLs for grain yield are in synteny with previously reported overdominant quantitative trait loci for grain yield in maize. A mechanism for the reproductive heterosis found in this study is suggested, in which grain yield increase is achieved by releasing the compensatory tradeoffs between biomass and reproductive output, and between seed number and weight. These results highlight the power of analyzing a diverse set of inbreds and their hybrids for unraveling hitherto unknown allelic interactions mediating heterosis.

  8. The healing of alkali-injured cornea is stimulated by a novel matrix regenerating agent (RGTA, CACICOL20): a biopolymer mimicking heparan sulfates reducing proteolytic, oxidative and nitrosative damage.

    Science.gov (United States)

    Cejkova, Jitka; Olmiere, Celine; Cejka, Cestmir; Trosan, Peter; Holan, Vladimir

    2014-04-01

    The efficacy of a chemically modified dextran - heparan sulfate mimicking regenerating agent (RGTA) on the healing of the rabbit cornea injured with alkali was examined. The eyes were injured with 0.15 N NaOH applied on the cornea or with 1.0 N NaOH using a 8 mm diameter filter paper disk. Then RGTA or placebo was applied on the cornea. In the last group of rabbits, corneas injured with the high alkali concentration were left without any treatment for four weeks; subsequently, the corneas were treated with RGTA or placebo. The central corneal thickness was measured using a pachymeter. The corneas were examined morphologically, immunohistochemically and for real time-PCR. Compared to control (unaffected) corneas, following the application of low alkali concentration the expression of urokinase-type plasminogen activator, metalloproteinase 9, nitric oxide synthase and xanthine oxidase was increased in the injured corneal epithelium of placebo-treated eyes, whereas the expression of antioxidant enzymes was reduced. Nitrotyrosine and malondialdehyde stainings appeared in the corneal epithelium. RGTA application suppressed the antioxidant/prooxidant imbalance and reduced the expression of the above-mentioned immunohistochemical markers. The corneal thickness increased after alkali injury, decreased during corneal healing after RGTA treatment faster than after placebo application. Following the injury with the high alkali concentration, corneal inflammation and neovascularization were highly pronounced in placebo-treated corneas, whereas in RGTA-treated corneas they were significantly supressed. When RGTA or placebo application was started later after alkali injury and corneas were ulcerated, subsequent RGTA treatment healed the majority of them. In conclusion, RGTA facilitates the healing of injured corneas via a reduction of proteolytic, oxidative and nitrosative damage.

  9. Penetration of 45Ca in rabbit cornea following the introduction of air in the anterior chamber and its paracenthesis and following experimental intraocular hypertension

    International Nuclear Information System (INIS)

    Votockova, J.; Obenberger, J.; Babicky, A.

    1977-01-01

    In one group of Chinchilla rabbits the aqueous humor was withdrawn and the anterior chamber was refilled with air; in a second group only simple paracenthesis and withdrawal were performed; in a third group of animals experimental intraocular hypertension was produced by means of a subconjunctival injection of hypertonic sodium chloride. Immediately after these operations, a solution of 45 CaCl 2 was intravenously injected, and the rabbits were sacrificed after an interval of 30 min or 120 min. The corneas were excised and the radioactivity in central parts (trephined discs of 8 mm in diameter) and in remaining peripheral parts was determined. In all groups the corneal radioactivity in operated eyes exceeded the values found in the contralateral corneas of not operated eyes, radioactivity in these eyes being equal to the radioactivity found in the corneas of not operated rabbits in the control group. Various possible explanations of the increase of corneal radioactivity in operated eyes are briefly discussed. (author)

  10. Locus of Control and Technology Adoption in Developing Country Agriculture

    DEFF Research Database (Denmark)

    Abay, Kibrom Araya; Blalock, Garrick; Berhane, Guush

    2017-01-01

    and psychological explanations for the low rates of adoption of profitable agricultural technologies in Sub-Saharan Africa. Our results highlight that improving farmers’ non-cognitive skills (locus of control) may facilitate technology adoption and agricultural transformation. More generally, the results suggest...

  11. AUTOMATIC GENERATION OF ROOT LOCUS PLOTS FOR LINEAR ...

    African Journals Online (AJOL)

    Design and analysis of control systems often become difficult due to the complexity of the system model and the design techniques involved. This paper presents the development of a Tools Box in Microsoft Excel for control engineer that uses root locus as a time domain technique for system design and analysis. The Tool ...

  12. Male-pattern baldness susceptibility locus at 20p11.

    NARCIS (Netherlands)

    Richards, J.B.; Yuan, X.; Geller, F.; Waterworth, D.; Bataille, V.; Glass, D.; Song, K.; Waeber, G.; Vollenweider, P.; Aben, K.K.H.; Kiemeney, L.A.L.M.; Walters, B.; Soranzo, N.; Thorsteinsdottir, U.; Kong, A.; Rafnar, T.; Deloukas, P.; Sulem, P.; Stefansson, H.; Stefansson, K.; Spector, T.D.; Mooser, V.

    2008-01-01

    We conducted a genome-wide association study for androgenic alopecia in 1,125 men and identified a newly associated locus at chromosome 20p11.22, confirmed in three independent cohorts (n = 1,650; OR = 1.60, P = 1.1 x 10(-14) for rs1160312). The one man in seven who harbors risk alleles at both

  13. (PLWHA): influence of social support, self-esteem, health locus

    African Journals Online (AJOL)

    Coping among people living with HIV/AIDS (PLWHA): influence of social support, self-esteem, health locus of control and gender. ... approach, social support should be in the front burner, society should be sensitized to the importance of social support that is culturally appropriate and behaviour modification focused.

  14. Relationship Among Achievement Motivation, Self-Esteem, Locus of ...

    African Journals Online (AJOL)

    The thrust of the study was to examine the relationship among achievement motivation, self-esteem, locus of control and academic performance of university students in a Nigerian University. The purpose was to determine the extent university student\\'s academic performance was influenced by these criterion variables.

  15. Locus of control and learning strategies as predictors of academic ...

    African Journals Online (AJOL)

    The aim of the research was to determine the relationships which exist between academic success, learning strategies and locus of control. In order to achieve this aim a small-scale quantitative study, utilising two inventories, was done. The first measuring instrument is the Learning and Study Strategies Inventory, which is ...

  16. Y-Chromosome short tandem repeat, typing technology, locus ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-07-08

    Jul 8, 2015 ... Y-Chromosome short tandem repeat, typing technology, locus information and allele frequency in different population: A review. Muhanned Abdulhasan Kareem1, Ameera Omran Hussein2 and Imad Hadi Hameed2*. 1Babylon University, Centre of Environmental Research, Hilla City, Iraq. 2Department of ...

  17. Influence of Locus Control on Real and Perceived Relationships ...

    African Journals Online (AJOL)

    They included the Nowicki-Strickland Internal – External Locus of Control Scale for children by Nowicki and Strickland (1973) and Emotional – Social Loneliness Inventory by Vincenzi and Grabosky, (1987). A cross sectional survey design was used while regression analysis and multivariate statistics were used in data ...

  18. Screening for genomic rearrangements at BRCA1 locus in Iranian ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... Home; Journals; Journal of Genetics; Volume 92; Issue 1. Screening for genomic rearrangements at BRCA1 locus in Iranian women with breast cancer using multiplex ligation-dependent probe amplification. Vahid R. Yassaee Babak Emamalizadeh Mir Davood Omrani. Research Note Volume 92 Issue 1 ...

  19. Gender, Age and Locus of Control as Correlates of Remedial ...

    African Journals Online (AJOL)

    Gender, Age and Locus of Control as Correlates of Remedial Learners' Attitude towards English Language. ... These findings have far-reaching implications for adult and non-formal education practitioners and other stakeholders interested in improving the lots of several learners out there, in English language. Keywords: ...

  20. Sex Differences in Locus of Control, Helplessness, Hopelessness, and Depression.

    Science.gov (United States)

    Kolotkin, Richard A.; And Others

    This experiment investigated: (1) relationships among locus of control, attributional style, and depression; (2) if a depressogenic attributional style could be empirically isolated; and (3) if reliable relationships existed between attribution and depression when depression was operationalized using different instruments. Subjects completed the…

  1. Demographic Determinants of Locus of Control among Medical ...

    African Journals Online (AJOL)

    The Levenson Multidimensional Locus of Control Inventory and a Socio - demographic data collection sheet were used to collect data from 262 (183 males and 79 females) students selected through convenience sampling. Data were th analyzed using the 16th version of the SPPS. Percentages, means, t-test and ANOVA ...

  2. Single locus complementary sex determination in Hymenoptera : an "unintelligent" design?

    NARCIS (Netherlands)

    Wilgenburg, Ellen van; Driessen, Gerard; Beukeboom, Leo W.

    2006-01-01

    The haplodiploid sex determining mechanism in Hymenoptera (males are haploid, females are diploid) has played an important role in the evolution of this insect order. In Hymenoptera sex is usually determined by a single locus, heterozygotes are female and hemizygotes are male. Under inbreeding,

  3. Single locus complementary sex determination in Hymenoptera: an "unintelligent" design?

    NARCIS (Netherlands)

    van Wilgenburg, E.; Driessen, G.J.J.; Beukeboom, L.W.

    2006-01-01

    The haplodiploid sex determining mechanism in Hymenoptera (males are haploid, females are diploid) has played an important role in the evolution of this insect order. In Hymenoptera sex is usually determined by a single locus, heterozygotes are female and hemizygotes are male. Under inbreeding,

  4. The Influence of Locus of Control on Student Financial Behavior

    Science.gov (United States)

    Britt, Sonya; Cumbie, Julie A.; Bell, Mary M.

    2013-01-01

    Data on psychological influences of financial behaviors has not been well addressed in student populations, which is concerning given the high levels of general and financial stress experienced by college students. The findings of this study indicate that college students with an external locus of control exhibit the worst financial behaviors.…

  5. Dealing with Malfunction: Locus of Control in Web-Conferencing

    Science.gov (United States)

    Klebl, Michael

    2014-01-01

    This paper considers how students deal with malfunctions that occur during the use of web conferencing systems in learning arrangements. In a survey among participants in online courses that make use of a web-conferencing system (N = 129), the relationship between a preference for internal or external locus of control and the perception of…

  6. Influences of peer relations and locus of control on students ...

    African Journals Online (AJOL)

    Effort to checkmate extravagance and maximize gain is the focus of all organizations more in this period of global financial crisis. There is need therefore to checkmate unnecessary financial spending. This study examines the influence of the variables, peer relations and locus of control, on such spending among University ...

  7. Exploring Learner Autonomy: Language Learning Locus of Control in Multilinguals

    Science.gov (United States)

    Peek, Ron

    2016-01-01

    By using data from an online language learning beliefs survey (n?=?841), defining language learning experience in terms of participants' multilingualism, and using a domain-specific language learning locus of control (LLLOC) instrument, this article examines whether more experienced language learners can also be seen as more autonomous language…

  8. A multi-locus phylogenetic evaluation of Diaporthe (Phomopsis)

    NARCIS (Netherlands)

    Udayanga, D.; Liu, X.; Crous, P.W.; McKenzie, E.H.C.; Chukeatirote, E.; Hyde, K.D.

    2012-01-01

    The genus Diaporthe (Phomopsis) includes important plant pathogenic fungi with wide host ranges and geographic distributions. In the present study, phylogenetic species recognition in Diaporthe is re-evaluated using a multi-locus phylogeny based on a combined data matrix of rDNA ITS, and partial

  9. Relationship between internet addiction and academic locus of ...

    African Journals Online (AJOL)

    The study identified the various internet activities engaged in by students in a Nigerian University and examined the relationship between internet addiction and their academic locus of control. The sample was made of 250 students selected from a University in Nigeria. An instrument tagged “Questionnaire on Students' ...

  10. Arousal, exploration and the locus coeruleus-norepinephrine system

    NARCIS (Netherlands)

    Jepma, Marieke

    2011-01-01

    The studies described in this thesis address a range of topics related to arousal, exploration, temporal attention, and the locus coeruleus-norepinephrine (LC-NE) system. Chapters 2 and 3 report two studies that investigated a recent theory about the role of the LC-NE system in the regulation of the

  11. Locus of Control and Likelihood of Nuclear War: Two Studies.

    Science.gov (United States)

    Erdahl, Paul; Rounds, James B.

    The Nuclear Locus of Control (NLOC) scales were constructed to assess beliefs as to whether nuclear war and nuclear policy decisions are, or can be, influenced by oneself, powerful others, or chance. Three scales measuring internal, powerful others, and chance nuclear LOC show internal consistency estimates (Cronbach's Alpha) of .87, .76, and .85,…

  12. Strengthening Locus Standi in Human Rights Litigation in Zimbabwe ...

    African Journals Online (AJOL)

    MJM Venter

    2016-05-30

    May 30, 2016 ... approach is likely to impact on the right to access to justice and human rights protection. 2. Locus standi ... Committee on Economic, Social and Cultural Rights General Comment 9: The. Domestic .... animosity towards an accused, in bad faith and without any warrant, were to rule that the question raised by ...

  13. Should Farmers' Locus of Control Be Used in Extension?

    Science.gov (United States)

    Nuthall, Peter L.

    2010-01-01

    To explore whether Farmers' Locus of Control (LOC) could be useful in agricultural extension programmes to improve managerial ability. This test records a farmer's belief in her/his control over production outcomes. A mail survey of 2300 New Zealand farmers was used to obtain a range of variables, and to measure their LOC using a question set…

  14. DNA marker mining of ILSTS035 microsatellite locus on ...

    Indian Academy of Sciences (India)

    Unknown

    We describe tests for detecting and locating quantitative trait loci (QTL) for traits in Hanwoo cattle. From results of a permutation test to detect QTL for marbling, we selected the microsatellite locus ILSTS035 on chromosome 6 for further analysis. K-means clustering analysis applied to five traits and nine DNA markers in ...

  15. Determination of the yield locus by means of temperature measurement

    NARCIS (Netherlands)

    Banabic, D.; Huetink, Han

    2006-01-01

    The paper presents a theoretical background of the thermo-graphical method of determining the yield locus. The analytical expression of the temperature variation of the specimen deformed in the elastic state is determined starting from the first law of thermodynamics. The experimental method for

  16. Inferring relationships between pairs of individuals from locus heterozygosities

    Directory of Open Access Journals (Sweden)

    Spinetti Isabella

    2002-11-01

    Full Text Available Abstract Background The traditional exact method for inferring relationships between individuals from genetic data is not easily applicable in all situations that may be encountered in several fields of applied genetics. This study describes an approach that gives affordable results and is easily applicable; it is based on the probabilities that two individuals share 0, 1 or both alleles at a locus identical by state. Results We show that these probabilities (zi depend on locus heterozygosity (H, and are scarcely affected by variation of the distribution of allele frequencies. This allows us to obtain empirical curves relating zi's to H for a series of common relationships, so that the likelihood ratio of a pair of relationships between any two individuals, given their genotypes at a locus, is a function of a single parameter, H. Application to large samples of mother-child and full-sib pairs shows that the statistical power of this method to infer the correct relationship is not much lower than the exact method. Analysis of a large database of STR data proves that locus heterozygosity does not vary significantly among Caucasian populations, apart from special cases, so that the likelihood ratio of the more common relationships between pairs of individuals may be obtained by looking at tabulated zi values. Conclusions A simple method is provided, which may be used by any scientist with the help of a calculator or a spreadsheet to compute the likelihood ratios of common alternative relationships between pairs of individuals.

  17. Response to selection in finite locus models with nonadditive effects

    NARCIS (Netherlands)

    Esfandyari, Hadi; Henryon, Mark; Berg, Peer; Thomasen, Jørn Rind; Bijma, Piter; Sørensen, Anders Christian

    2017-01-01

    Under the finite-locus model in the absence of mutation, the additive genetic variation is expected to decrease when directional selection is acting on a population, according to quantitative-genetic theory. However, some theoretical studies of selection suggest that the level of additive

  18. Locus of control and investment in risky assets

    NARCIS (Netherlands)

    Salamanca Acosta, Nicolas; de Grip, A.; Fouarge, Didier; Montizaan, Raymond

    2016-01-01

    We show that household heads with a strong internal economic locus of control are more likely to hold equity and hold a larger share of equity in their investment portfolio. This relation holds when we control for economic preferences and possible confounders such as financial literacy,

  19. 40 CFR 798.5195 - Mouse biochemical specific locus test.

    Science.gov (United States)

    2010-07-01

    ...-induced variants are bred to determine the genetic nature of the change. (f) Data and reports—(1... SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Genetic Toxicity § 798.5195 Mouse...) A biochemical specific locus mutation is a genetic change resulting from a DNA lesion causing...

  20. Emotional intelligence and locus of control of adult patients with ...

    African Journals Online (AJOL)

    Background: This article investigates emotional intelligence and locus of control in an adult breast cancer population receiving treatment. Gaining insight into these constructs will contribute to improving breast cancer patients' psychological well-being and to reducing physical vulnerability to disease before and during ...

  1. The Locus of Metaphorical Persuasion: An Empirical Test.

    Science.gov (United States)

    Hitchon, Jacqueline C.

    1997-01-01

    Investigates whether the locus of persuasion of the metaphor "A is B" lies in the valence of B, as widely assumed, or in the valence of the metaphor ground, what A and B share. Indicates that global affect toward B does not transfer onto A and that metaphorical persuasion is a distinct process meriting further investigation. (SR)

  2. Social support, locus of control, and psychological well-being

    NARCIS (Netherlands)

    van der Zee, KI; Buunk, BP; Sanderman, R

    1997-01-01

    Social support seems to be positively related to psychological well-being. Studies have shown that individual differences exist in the ability to mobilize and use sources of support. The current study focused on locus of control as a personality factor that might be related to this ability, In 2

  3. Locus of Control and Neuropsychological Performance in Chronic Alcoholics.

    Science.gov (United States)

    Shelton, M. D.; And Others

    1982-01-01

    Examined correlated neuropsychological performance in male chronic alcoholics and non-alcoholic controls. Results showed external locus of control (LOC-E) scores to predict performance on neuropsychological tests in alcoholics but not in controls. Suggests the LOC-E variables cannot account for the widespread differences between the groups on…

  4. New distal marker closely linked to the fragile X locus

    NARCIS (Netherlands)

    Hulsebos, T. J.; Oostra, B. A.; Broersen, S.; Smits, A.; van Oost, B. A.; Westerveld, A.

    1991-01-01

    We have isolated II-10, a new X-chromosomal probe that identifies a highly informative two-allele TaqI restriction fragment length polymorphism at locus DXS466. Using somatic cell hybrids containing distinct portions of the long arm of the X chromosome, we could localize DXS466 between DXS296 and

  5. Beneficial effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea

    Directory of Open Access Journals (Sweden)

    Fan Xiao

    2018-05-01

    Full Text Available Present investigation evaluates the effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea. Briefly, electron spine resonance was used for the estimation of radical scavenging activity of daidzin and COX Fluorescent Activity Assay Kit was used for the estimation of PGS activity. Dry eye rat model was developed by removing the lacrimal gland and effect of daidzin was evaluated in dry eye rat model by estimating the fluorescein score, tear volume and expressions of heme oxigenase (HO-1, TNF α, Interlukin 6 (IL-6, matrix metallopeptidase 9 (MMP-9 and PGS-2. Result of the present study suggested that daidzin possess tyrosyl radical scavenging activity and thereby decreases the oxidative stress. Activity of PGS significantly increases in dry eye which was inhibited by daidzin treatment due to competitive inhibition of PGS. It also recovers the tear volume in dry eye rat model in which lacrimal gland was removed. Thus corneal erosion was improved by daidzin in dry eye rat model. Thus present study concludes that treatment with daidzin protects the cornea in dry eye rat model by suppression inflammation and oxidative stress. Keywords: Daidzin, Dry eye, Radical scavenging activity, Inflammation

  6. Beneficial effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea.

    Science.gov (United States)

    Xiao, Fan; Cui, Hua; Zhong, Xiao

    2018-05-01

    Present investigation evaluates the effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea. Briefly, electron spine resonance was used for the estimation of radical scavenging activity of daidzin and COX Fluorescent Activity Assay Kit was used for the estimation of PGS activity. Dry eye rat model was developed by removing the lacrimal gland and effect of daidzin was evaluated in dry eye rat model by estimating the fluorescein score, tear volume and expressions of heme oxigenase (HO-1), TNF α, Interlukin 6 (IL-6), matrix metallopeptidase 9 (MMP-9) and PGS-2. Result of the present study suggested that daidzin possess tyrosyl radical scavenging activity and thereby decreases the oxidative stress. Activity of PGS significantly increases in dry eye which was inhibited by daidzin treatment due to competitive inhibition of PGS. It also recovers the tear volume in dry eye rat model in which lacrimal gland was removed. Thus corneal erosion was improved by daidzin in dry eye rat model. Thus present study concludes that treatment with daidzin protects the cornea in dry eye rat model by suppression inflammation and oxidative stress.

  7. Quantitative & qualitative analysis of endothelial cells of donor cornea before & after penetrating keratoplasty in different pathological conditions

    Directory of Open Access Journals (Sweden)

    Aruna K.R. Gupta

    2016-01-01

    Full Text Available Background & objectives: Endothelial cells of the donor cornea are known to be affected quantitatively and qualitatively in different pathological conditions after penetrating keratoplasty (PK and this has direct effect on the clarity of vision obtained after PK. This study was undertaken to analyze the qualitative and quantitative changes in donor endothelial cells before and after PK in different pathological conditions. Methods: A prospective investigational analysis of 100 consecutive donor corneas used for penetrating keratoplasty between June 2006 and June 2008, was conducted. The patients were evaluated on the first day, at the end of first week, first month, third and six months and one year. Results: A decrease was observed in endothelial cell count in all pathological conditions. After one year of follow up the loss was 33.1 per cent in corneal opacity, 45.9 per cent in acute infective keratitis (AIK, 58.5 per cent in regrafts, 28.5 per cent in pseudophakic bullous keratopathy (PBK, 37 per cent in descemetocele, 27 per cent in keratoconus and 35.5 per cent in aphakic bullous keratopathy (ABK cases. Interpretation & conclusions: The endothelial cell loss was highest in regraft cases which was significant (P<0.05, while the least endothelial cell loss was seen in keratoconus cases. The cell loss was associated with increase in coefficient of variation (CV, i.e. polymegathism and pleomorphism. Inspite of this polymegathism and pleomorphism, the clarity of the graft was maintained.

  8. Visual outcomes after deep anterior lamellar keratoplasty using donor corneas without removal of Descemet membrane and endothelium

    Directory of Open Access Journals (Sweden)

    Tatiana Moura Bastos Prazeres

    Full Text Available ABSTRACT Purpose: The optical quality of the interface after deep anterior lamellar keratoplasty (DALK using the big-bubble technique has been shown to be excellent, leading to results comparable to penetrating keratoplasty. However, there is little in the literature with respect to the controversy surrounding the preparation of the donor cornea. The purpose of this study was to evaluate visual acuity (VA in patients with keratoconus who underwent DALK without removal of the donor graft endothelium. Methods: The records of 90 patients who underwent DALK without the removal of the Descemet membrane (DM and endothelium were retrospectively reviewed. Data collected included uncorrected VA (UCVA and spectacle-corrected VA (SCVA at 7, 30, 180 days, and 1 year postoperatively. Contact lens-corrected visual acuity (CLVA was evaluated after 1 year of the procedure. Results: UCVA was significantly better than preoperative values at 7 days (p<0.001, 30 days (p<0.001, 180 days (p<0.001, and 1 year (p<0.001 after surgery. The 1-year postoperative mean SCVA and CLVA also improved when compared with preoperative SCVA (p<0.001 for both. Conclusions: DALK utilizing donor corneas with attached Descemet membrane and endothelium results in satisfactory VA in patients with keratoconus.

  9. Behaviour of glutathione in the cornea epithelium of cattle and rabbits under the influence of infrared radiation

    International Nuclear Information System (INIS)

    Scharsich, G.

    1978-01-01

    After creating a keratitis photoelectrica by means of a mercury/quartz analysis lamp, the concentration of GSH (glutathion, reduced) and GSSG (glutathion, oxidised) in the cornea epithelium of cattle and of rabbits at different times after irradiation was determined. The question of whether ultraviolet radiation considerably influences the GSH/GSSG quotient before the keratitis photoelectrica is fully formed morphologically, could be answered as follows: There is no considerable change in the GSH/GSSG quotient during the first 7-10 hours after the irradiation. Then, when there is, also morphologically, a keratitis photoelectrica, the GSH/GSSG quotient is doubled. The linkage of the GSH/GSSG system and hexosephosphatshunt via the NADP/NADPH system leads us to the conclusion that irradiation does not cause any direct changes in the GSH/GSSG system. Only when the cornea epithelium visably disintegrates an increased reduction of the glutathion occurs, like in several other damaging influences. Thus the found increase of the GSH/GSSG quotient 7-10 hours after ultraviolet irradiation might be unspecific. (orig./AJ) [de

  10. Analysis of two precipitation methods on the yield, structural features and activity of sulfated polysaccharides from Gracilaria cornea (Rhodophyta

    Directory of Open Access Journals (Sweden)

    Ricardo Basto Souza

    2015-03-01

    Full Text Available The global demand for natural products from seaweeds has increased worldwide; however, no description of the use of isoamly alcohol (IAA for obtaining of sulfated polysaccharides (SPs has been reported. We investigated the efficiency of two precipitation methods (M in obtaining SPs from the red seaweed Gracilaria cornea. SPs enzymatically isolated were concentrated with cetylpyridinium chloride (M I or IAA (M II and extracts were examined with regard to their yield, structural features and in vitro effects on the activated partial thromboplastin time (APTT using normal human plasma and standard heparin (193 IU mg-1. Yield difference reached 12.99%. Quantitative determination of sulfate was similar between the two methods (̴ 26%, but extracts revealed different pattern on charge density by agarose gel electrophoresis. Whereas both extracts revealed as agarocolloids, alternative M II was also efficient for lipids, proteins and nucleic acids according to the infrared analysis. Extracts had virtually no effect on APPT (1.95 and 2 IU mg-1 for M I and M II, respectively. The results revealed IAA as an alternative solvent for obtaining SPs from the red seaweed G. cornea, depending on the industry’ usage criterion.

  11. Nucleation and growth of apatite on NaOH-treated PEEK, HDPE and UHMWPE for artificial cornea materials.

    Science.gov (United States)

    Pino, M; Stingelin, N; Tanner, K E

    2008-11-01

    The skirt of an artificial cornea must integrate the implant to the host sclera, a major failure of present devices. Thus, it is highly desirable to encourage the metabolic activity of the cornea by using more bioactive, flexible skirt materials. Here we describe attempts to increase the bioactivity of polyether ether ketone (PEEK), high-density polyethylene (HDPE) and ultra-high molecular weight polyethylene (UHMWPE) films. The effectiveness of different strength NaOH pre-treatments to initiate apatite deposition on PEEK, HDPE and UHMWPE is investigated. We find that exposure of PEEK, HDPE and UHMWPE films to NaOH solutions induces the formation of potential nuclei for apatite (calcium phosphate), from which the growth of an apatite coating is stimulated when subsequently immersing the polymer films in 1.5 strength Simulated Body Fluid (SBF). As immersion time in SBF increases, further nucleation and growth produces a thicker and more compact apatite coating that can be expected to be highly bioactive. Interestingly, the apatite growth is found to also be dependent on both the concentration of NaOH solution and the structure of the polymer surface.

  12. Prevalence of spheroidal degeneration of cornea and its association with other eye diseases in tribes of Western Rajasthan

    Directory of Open Access Journals (Sweden)

    Amit Mohan

    2017-01-01

    Full Text Available Purpose: To determine the prevalence of spheroidal degeneration of cornea (SDC and its association with other eye diseases in the tribes of South-West Rajasthan. Methods: A total of 5012 patients were examined on slit lamp for the diagnosis of SDC. Diagnosis of SDC was made based on presence of amber granules in the superficial stroma of peripheral interpalpebral cornea with increasing opacification, coalescence and central spread or nodular and hazy surrounding stroma and divided in three stages. Results: The prevalence of SDC was 10.7%. Around 55% of the total of 535 cases examined were found to have Stage I followed by Stage II (32% and Stage III (13%. The prevalence is greatest in both men and women over 70 years of age. The severity of SDC is greater in men. SDC was significantly associated with pterygium and pseudocapsular exfoliation. Conclusion: Extreme temperature, low humidity, dust, high wind, and microtrauma caused by sand particles are the probable etiologies for higher prevalence of this kind of degeneration in this region.

  13. Mast Cell Activation Protects Cornea by Promoting Neutrophil Infiltration via Stimulating ICAM-1 and Vascular Dilation in Fungal Keratitis.

    Science.gov (United States)

    Xie, Yanting; Zhang, Hongmin; Liu, Susu; Chen, Guoming; He, Siyu; Li, Zhijie; Wang, Liya

    2018-05-30

    The role of mast cells (MCs) in fungal infection is largely unknown. This study was to explore a protective role and mechanism of MCs in fungal keratitis. Experimental fungal keratitis (FK) mouse model was developed. Mice untreated (UT) or receiving corneal wound without fungal infection (Mock) were used as controls. Large number of connective tissue MCs was found in normal mice. MC activation with degranulation was largely observed, and the percentage of degranulated/total cells was high in FK. Dilated limbal vasculature with increased permeability, as well as largely infiltrated neutrophils with stimulated ICAM-1 protein levels were observed in corneas of FK mice, when compared with Mock and UT mice. Interestingly, pretreatment with cromolyn sodium (Block) significantly blocked MC degranulation, dramatically suppressed vascular dilation and permeability, and markedly reduced neutrophil infiltration with lower ICAM-1 levels in FK mice at 6-24 hours. Furthermore, the Block mice manifested prolonged disease course, increased pathological damage, and vigorous fungus growth, with much higher corneal perforation rate than FK mice at 72 h. These findings reveal a novel phenomenon that MCs play a vital role in protecting cornea against fungal infection through degranulation that promotes neutrophil infiltration via stimulating ICAM-1 production and limbal vascular dilation and permeability.

  14. Rocking media over ex vivo corneas improves this model and allows the study of the effect of proinflammatory cytokines on wound healing.

    Science.gov (United States)

    Deshpande, Pallavi; Ortega, Ílida; Sefat, Farshid; Sangwan, Virender S; Green, Nicola; Claeyssens, Frederik; MacNeil, Sheila

    2015-02-05

    The aim of this work was to develop an in vitro cornea model to study the effect of proinflammatory cytokines on wound healing. Initial studies investigated how to maintain the ex vivo models for up to 4 weeks without loss of epithelium. To study the effect of cytokines, corneas were cultured with the interleukins IL-17A, IL-22, or a combination of IL-17A and IL-22, or lipopolysaccharide (LPS). The effect of IL-17A on wound healing was then examined. With static culture conditions, organ cultures deteriorated within 2 weeks. With gentle rocking of media over the corneas and carbon dioxide perfusion, the ex vivo models survived for up to 4 weeks without loss of epithelium. The cytokine that caused the most damage to the cornea was IL-17A. Under static conditions, wound healing of the central corneal epithelium occurred within 9 days, but only a single-layered epithelium formed whether the cornea was exposed to IL-17A or not. With rocking of media gently over the corneas, a multilayered epithelium was achieved 9 days after wounding. In the presence of IL-17A, however, there was no wound healing evident. Characterization of the cells showed that wherever epithelium was present, both differentiated cells and highly proliferative cells were present. We propose that introducing rocking to extend the effective working life of this model and the introduction of IL-17A to this model to induce aspects of inflammation extend its usefulness to study the effects of agents that influence corneal regeneration under normal and inflamed conditions. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  15. Examining the effect of the CaMKII inhibitor administration in the locus coeruleus on the naloxone-precipitated morphine withdrawal signs in rats.

    Science.gov (United States)

    Navidhamidi, M; Semnanian, S; Javan, M; Goudarzvand, M; Rohampour, K; Azizi, H

    2012-01-15

    Drug addiction is an occurrence with physiological, psychological, and social outcomes. Repeated drug exposure causes neuronal adaptations and dependency. It has been shown that CaMKIIα enzyme contributes to morphine dependency. The locus coeruleus nucleus has been implied in the morphine withdrawal syndrome. This research focuses on the behavioral and molecular adaptations that occur in the locus coeruleus neurons in response to the chronic morphine exposure. Adult male Wistar rats were injected by morphine sulfate (10 mg/kg/s.c.) at an interval of 12 h for a period of nine subsequent days. On the tenth day, naloxone (1 mg/kg/i.p.) was injected 2 h after the morphine administration. Somatic withdrawal signs were investigated for 30 min. We concluded that the inhibition of CaMKIIα by administration of KN-93, the specific inhibitor of this enzyme, significantly attenuated some of the withdrawal signs. In molecular method, the expression of CaMKIIα protein has been enhanced in locus coeruleus of the morphine dependent rats. These findings indicate that CaMKIIα may be involved in the modulation of the naloxone-induced withdrawal syndrome, and treatment with KN-93 may have some effects on this system. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. DMPD: The Lps locus: genetic regulation of host responses to bacteriallipopolysaccharide. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 10669111 The Lps locus: genetic regulation of host responses to bacteriallipopolysaccharide. Qur...e The Lps locus: genetic regulation of host responses to bacteriallipopolysaccharide. Authors Qur

  17. [Relationship between work locus of control and occupational stress in oil workers].

    Science.gov (United States)

    Meng, Xian-Hai; He, Ya-Hui; Yu, Shan-Fa; Qi, Xiu-Ying

    2008-12-01

    To investigate general states of the work locus of control and explore the relationship between work locus of control and occupational stress in oil workers. 582 oil workers were investigated by using the General Questionnaire and Occupational Stress Measure Inventory. There were significant differences in WCLS score between two age groups (= 30 years old group and locus of control; values of role ambiguity, working prospect, depression and social support were higher in the group of external locus of control (P locus of control had positive relation with role ambiguity, working prospect, depression, and social support, and negative with interpersonal relationship, promotion, participation, task consistency, challenge, job satisfaction, mental health, self-esteem and coping strategies. In the regression analysis, work locus of control was the major predictive factor of work satisfaction. Work locus of control is associated with many occupational stress factors. The group of extrinsic work locus of control experience more stress in oil workers.

  18. VRP09 Reduction of Corneal Scarring Following Blast and Burn Injuries to Cornea Using siRNAs Targeting TGFb and CTGF

    Science.gov (United States)

    2013-03-01

    aSMA ) synthesis. Second, we proposed to develop an advanced ex vivo organ culture system using viable explants of rabbit corneas, and assess the...effect of the most effective triple siRNA combination for reduction of target genes, collagen and alpha smooth muscle actin ( aSMA ) in rabbit corneas...targeting three key genes (TGFb, TGFbRII, and CTGF) that synergistically reduces the level of mRNAs for type I collagen gene and aSMA by >95% without

  19. Defective replication initiation results in locus specific chromosome breakage and a ribosomal RNA deficiency in yeast.

    Directory of Open Access Journals (Sweden)

    Joseph C Sanchez

    2017-10-01

    Full Text Available A form of dwarfism known as Meier-Gorlin syndrome (MGS is caused by recessive mutations in one of six different genes (ORC1, ORC4, ORC6, CDC6, CDT1, and MCM5. These genes encode components of the pre-replication complex, which assembles at origins of replication prior to S phase. Also, variants in two additional replication initiation genes have joined the list of causative mutations for MGS (Geminin and CDC45. The identity of the causative MGS genetic variants strongly suggests that some aspect of replication is amiss in MGS patients; however, little evidence has been obtained regarding what aspect of chromosome replication is faulty. Since the site of one of the missense mutations in the human ORC4 alleles is conserved between humans and yeast, we sought to determine in what way this single amino acid change affects the process of chromosome replication, by introducing the comparable mutation into yeast (orc4Y232C. We find that yeast cells with the orc4Y232C allele have a prolonged S-phase, due to compromised replication initiation at the ribosomal DNA (rDNA locus located on chromosome XII. The inability to initiate replication at the rDNA locus results in chromosome breakage and a severely reduced rDNA copy number in the survivors, presumably helping to ensure complete replication of chromosome XII. Although reducing rDNA copy number may help ensure complete chromosome replication, orc4Y232C cells struggle to meet the high demand for ribosomal RNA synthesis. This finding provides additional evidence linking two essential cellular pathways-DNA replication and ribosome biogenesis.

  20. Defective replication initiation results in locus specific chromosome breakage and a ribosomal RNA deficiency in yeast.

    Science.gov (United States)

    Sanchez, Joseph C; Kwan, Elizabeth X; Pohl, Thomas J; Amemiya, Haley M; Raghuraman, M K; Brewer, Bonita J

    2017-10-01

    A form of dwarfism known as Meier-Gorlin syndrome (MGS) is caused by recessive mutations in one of six different genes (ORC1, ORC4, ORC6, CDC6, CDT1, and MCM5). These genes encode components of the pre-replication complex, which assembles at origins of replication prior to S phase. Also, variants in two additional replication initiation genes have joined the list of causative mutations for MGS (Geminin and CDC45). The identity of the causative MGS genetic variants strongly suggests that some aspect of replication is amiss in MGS patients; however, little evidence has been obtained regarding what aspect of chromosome replication is faulty. Since the site of one of the missense mutations in the human ORC4 alleles is conserved between humans and yeast, we sought to determine in what way this single amino acid change affects the process of chromosome replication, by introducing the comparable mutation into yeast (orc4Y232C). We find that yeast cells with the orc4Y232C allele have a prolonged S-phase, due to compromised replication initiation at the ribosomal DNA (rDNA) locus located on chromosome XII. The inability to initiate replication at the rDNA locus results in chromosome breakage and a severely reduced rDNA copy number in the survivors, presumably helping to ensure complete replication of chromosome XII. Although reducing rDNA copy number may help ensure complete chromosome replication, orc4Y232C cells struggle to meet the high demand for ribosomal RNA synthesis. This finding provides additional evidence linking two essential cellular pathways-DNA replication and ribosome biogenesis.

  1. Theoretical perspectives on central chemosensitivity: CO2/H+-sensitive neurons in the locus coeruleus.

    Directory of Open Access Journals (Sweden)

    Maria C Quintero

    2017-12-01

    Full Text Available Central chemoreceptors are highly sensitive neurons that respond to changes in pH and CO2 levels. An increase in CO2/H+ typically reflects a rise in the firing rate of these neurons, which stimulates an increase in ventilation. Here, we present an ionic current model that reproduces the basic electrophysiological activity of individual CO2/H+-sensitive neurons from the locus coeruleus (LC. We used this model to explore chemoreceptor discharge patterns in response to electrical and chemical stimuli. The modeled neurons showed both stimulus-evoked activity and spontaneous activity under physiological parameters. Neuronal responses to electrical and chemical stimulation showed specific firing patterns of spike frequency adaptation, postinhibitory rebound, and post-stimulation recovery. Conversely, the response to chemical stimulation alone (based on physiological CO2/H+ changes, in the absence of external depolarizing stimulation, showed no signs of postinhibitory rebound or post-stimulation recovery, and no depolarizing sag. A sensitivity analysis for the firing-rate response to the different stimuli revealed that the contribution of an applied stimulus current exceeded that of the chemical signals. The firing-rate response increased indefinitely with injected depolarizing current, but reached saturation with chemical stimuli. Our computational model reproduced the regular pacemaker-like spiking pattern, action potential shape, and most of the membrane properties that characterize CO2/H+-sensitive neurons from the locus coeruleus. This validates the model and highlights its potential as a tool for studying the cellular mechanisms underlying the altered central chemosensitivity present in a variety of disorders such as sudden infant death syndrome, depression, and anxiety. In addition, the model results suggest that small external electrical signals play a greater role in determining the chemosensitive response to changes in CO2/H+ than previously

  2. A cut locus for finite graphs and the farthest point mapping

    DEFF Research Database (Denmark)

    Maddaloni, Alessandro; Zamfirescu, Carol T.

    2016-01-01

    We reflect upon an analogue of the cut locus, a notion classically studied in Differential Geometry, for finite graphs. The cut locus C(x) of a vertex x shall be the graph induced by the set of all vertices y with the property that no shortest path between x and z, z≠y, contains y. The cut locus ...

  3. Reframing Student Affairs Leadership: An Analysis of Organizational Frames of Reference and Locus of Control

    Science.gov (United States)

    Tull, Ashley; Freeman, Jerrid P.

    2011-01-01

    Examined in this study were the identified frames of reference and locus of control used by 478 student affairs administrators. Administrator responses were examined to identify frames of reference most commonly used and their preference order. Locus of control most commonly used and the relationship between frames of reference and locus of…

  4. Locus of Control in Offenders and Alleged Offenders with Learning Disabilities

    Science.gov (United States)

    Goodman, Wendy; Leggett, Janice; Garrett, Tanya

    2007-01-01

    Locus of control can be a useful measure of treatment outcome in offenders from the general population. However, there is little information regarding locus of control and offenders with learning disabilities. Existing measures of locus of control use complex language and abstract ideas that may not be accessible to individuals in this group. A…

  5. Rasch Analysis of the Locus-of-Hope Scale. Brief Report

    Science.gov (United States)

    Gadiana, Leny G.; David, Adonis P.

    2015-01-01

    The Locus-of-Hope Scale (LHS) was developed as a measure of the locus-of-hope dimensions (Bernardo, 2010). The present study adds to the emerging literature on locus-of-hope by assessing the psychometric properties of the LHS using Rasch analysis. The results from the Rasch analyses of the four subscales of LHS provided evidence on the…

  6. On the Relation of Locus of Control and L2 Reading and Writing Achievement

    Science.gov (United States)

    Ghonsooly, Behzad; Shirvan, Majid Elahi

    2011-01-01

    Locus of control, a psychological construct, has been the focus of attention in recent decades. Psychologists have discussed the effect of locus of control on achieving life goals in social/psychological interactions. While learning a foreign language involves both social interactions and psychological processes, the role and relation of locus of…

  7. Short-term visual result after simultaneous photorefractive keratectomy and small-aperture cornea inlay implantation

    Directory of Open Access Journals (Sweden)

    Moshirfar M

    2016-11-01

    Full Text Available Majid Moshirfar,1,2 Ryan T Wallace,3 David F Skanchy,4 Jordan D Desautels,5 Steven H Linn,1 Phillip C Hoopes Jr,1 Daniel S Durrie1,6 1Hoopes, Durrie, Rivera, Research Center, Hoopes Vision, Draper, UT, 2Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT, 3Brigham Young University, Provo, UT, 4McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, 5Tufts University School of Medicine, Boston, MA, 6Durrie Vision, Overland Park, KS, USA Purpose: To report the short-term results of simultaneous photorefractive keratectomy (PRK and small-aperture cornea inlay implantation (KAMRA surgery in treating presbyopia. Methods: Simultaneous PRK and KAMRA inlay surgery was performed on 21 patients from July 2015 to March 2016. Follow-up exams were conducted at 1, 3, and 6 months postoperatively. Our patients were also divided preoperatively into three categories: myopic, hyperopic, and emmetropic. Over the 6-month period, the main outcome measures were uncorrected near visual acuity (UNVA, changes in best-corrected distance visual acuity, and mean spherical equivalent refraction. Results: At 6-month follow-up, 83% (10/12 of patients had a monocular UNVA of 20/40 or better, and 75% had a binocular UNVA of 20/40 (J5 or better. At 6 months, the overall mean refractive spherical equivalent (MRSE was -0.60 D (±0.42 standard deviation [SD], range: -1.38 to -0.13 with a mean change of -0.43 D (±1.19 SD, range: -1.5 to 2.63 compared to preoperative data. Overall, 91% (10/11 of patients were within a ±0.5 D range of our target -0.75 D for KAMRA use. One-hundred percent (5/5 of the hyperopes, 50% (1/2 of emmetropes, and 100% (4/4 of myopes met the targeted range. At 6 months, the MRSE for the hyperopic subgroup (n=5 was 0.33 D (±0.20 SD, the MRSE for the emmetropic subgroup (n=2 was -1.19 D (±0.19 SD, and the MRSE for the myopic

  8. Linkage analysis in a large Swedish family supports the presence of a susceptibility locus for adenoma and colorectal cancer on chromosome 9q22.32-31.1

    DEFF Research Database (Denmark)

    Skoglund, J; Djureinovic, T; Zhou, X-L

    2006-01-01

    BACKGROUND: The best known hereditary colorectal cancer syndromes, familial adenomatous polyposis (FAP) and hereditary non-polyposis colorectal cancer (HNPCC), constitute about 2% of all colorectal cancers, and there are at least as many non-FAP, non-HNPCC cases where the family history suggests...... a dominantly inherited colorectal cancer risk. Recently, a locus on chromosome 9q22.2-31.2 was identified by linkage analysis in sib pairs with colorectal cancer or adenoma. METHODS: Linkage analysis for the suggested locus on chromosome 9 was carried out in an extended Swedish family. This family had...... previously been investigated but following the identification of adenomas in several previously unaffected family members, these subjects were now considered to be gene carriers. RESULTS: In the present study, we found linkage of adenoma and colorectal cancer to chromosome 9q22.32-31.1 with a multipoint LOD...

  9. Allelic variations at the haploid TBX1 locus do not influence the cardiac phenotype in cases of 22q11 microdeletion.

    Science.gov (United States)

    Voelckel, Marie-Antoinette; Girardot, Lydie; Giusiano, Bernard; Levy, Nicolas; Philip, Nicole

    2004-01-01

    Microdeletion at the 22q11 locus is characterised by a high clinical variability. Congenital heart defects (CHD) are the most life-threatening manifestations of the syndrome and affect approximately 50% of patients carrying the deleted chromosome 22. The causes of this phenotype variability remain unknown although several hypotheses have been raised. It has been suggested that allelic variations at the haploid locus could modify the phenotypic expression. Regarding this hypothesis, TBX1 was thought to be a major candidate to the cardiac phenotype or its severity in patients carrying the 22q11 microdeletion. A mutational screening was performed in this gene, in a series of 39 deleted patients, with and without CHD. The results indicate that mutations in TBX1 are not likely to be involved in the cardiac phenotype observed in del22q11 patients.

  10. Characterization of a Multipeptide Lantibiotic Locus in Streptococcus pneumoniae.

    Science.gov (United States)

    Maricic, Natalie; Anderson, Erica S; Opipari, AnneMarie E; Yu, Emily A; Dawid, Suzanne

    2016-01-26

    Bacterial communities are established through a combination of cooperative and antagonistic interactions between the inhabitants. Competitive interactions often involve the production of antimicrobial substances, including bacteriocins, which are small antimicrobial peptides that target other community members. Despite the nearly ubiquitous presence of bacteriocin-encoding loci, inhibitory activity has been attributed to only a small fraction of gene clusters. In this study, we characterized a novel locus (the pld locus) in the pathogen Streptococcus pneumoniae that drives the production of a bacteriocin called pneumolancidin, which has broad antimicrobial activity. The locus encodes an unusual tandem array of four inhibitory peptides, three of which are absolutely required for antibacterial activity. The three peptide sequences are similar but appear to play distinct roles in regulation and inhibition. A modification enzyme typically found in loci encoding a class of highly modified bacteriocins called lantibiotics was required for inhibitory activity. The production of pneumolancidin is controlled by a two-component regulatory system that is activated by the accumulation of modified peptides. The locus is located on a mobile element that has been found in many pneumococcal lineages, although not all elements carry the pld genes. Intriguingly, a minimal region containing only the genes required for pneumolancidin immunity was found in several Streptococcus mitis strains. The pneumolancidin-producing strain can inhibit nearly all pneumococci tested to date and provided a competitive advantage in vivo. These peptides not only represent a unique strategy for bacterial competition but also are an important resource to guide the development of new antimicrobials. Successful colonization of a polymicrobial host surface is a prerequisite for the subsequent development of disease for many bacterial pathogens. Bacterial factors that directly inhibit the growth of neighbors

  11. Frank-ter Haar syndrome with unusual clinical features.

    Science.gov (United States)

    Dundar, Munis; Saatci, Cetin; Tasdemir, Sener; Akcakus, Mustafa; Caglayan, Ahmet Okay; Ozkul, Yusuf

    2009-01-01

    Frank-ter Haar syndrome first recognized by Frank et al. [Y. Frank, M. Ziprkowski, A. Romano, R. Stein, M.B. Katznelson, B. Cohen, R.M. Goodman, Megalocornea associated with multiple skeletal anomalies: a new genetic syndrome?, J. Genet. Hum. 21 (1973) 67-72.] and subsequently confirmed by ter Haar et al. [B. Ter Haar, B. Hamel, J. Hendriks, J. de Jager, Melnick-Needles syndrome: indication for an autosomal recessive form, Am. J. Med. Genet. 13 (1982) 469-477.]. The main clinical features of the syndrome are brachycephaly, wide fontanels, prominent forehead, hypertelorism, prominent eyes, macro cornea with or without glaucoma, full cheeks, small chin, bowing of the long bones, and flexion deformity of the fingers [S.M. Maas, H. Kayserili, J. Lam, M.Y. Apak, R.C. Hennekam, Further delineation of Frank-ter Haar syndrome, Am. J. Med. Genet. 131 (2004) 127-133.]. We report a child with Frank-ter Haar syndrome presenting unusual clinical features. Hypopigmented areas in hair, bilateral adducted thumb, bilateral contractures in elbows and pelvic limb, atrial septal defect have not been described previously in the literature. Our patient also had double-outlet right ventricle.

  12. Comparison of seropositivity of human immunodeficiency virus, hepatitis B virus, hepatitis C virus, and syphilis among Hospital Cornea Retrieval Programme-Donors versus voluntary cornea donors at a large eye bank in Eastern India.

    Science.gov (United States)

    Basak, Soham; Basak, Samar K; Biswas, Bani

    2017-11-01

    To compare the serology profile of donors from Hospital Cornea Retrieval Programme-donors (HCRP-D) and voluntary cornea donors (VC-D) from a large eye bank in Eastern India. This is a retrospective analysis of donor details from January 2011 to December 2016. Donor demographics, cause of death, and serology reports were compiled. Postmortem blood was tested for human immunodeficiency virus 1 and 2 (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis using government-approved kits as per the National Programme for Control of Blindness Standards of Eye Banking. Donors for whom serology was not possible were excluded. A total of 4300 of 4353 donors were included of which 74.3% were hospital donors and 25.7% were voluntary donors. A total of 93 (2.2%) donors with 94 seropositive reports were noted: 79 (84.9%) from HCRP-D and 14 (15.1%) from VC-D which was statistically significantly higher (P = 0.02). Among seropositive reports, HIV, HBV, HCV, and syphilis accounted for 12 (12.8%), 38 (40.4%), 36 (38.3%), and eight (8.5%), respectively. There was no correlation between the cause of death and seropositivity. A statistically significant decreasing trend in seroprevalence among hospital donors was observed over the years (5.3% in 2011 to 1.4% in 2016; P = 0.004). Two (0.47%) of 421 hospital donors with prior negative serology were found to be seropositive. Seropositive rates are significantly higher among hospital donors in spite of medical prescreening compared to nonscreened voluntary donors. Serology should be repeated even when prior reports are available.

  13. Comparison of seropositivity of human immunodeficiency virus, hepatitis B virus, hepatitis C virus, and syphilis among Hospital Cornea Retrieval Programme-Donors versus voluntary cornea donors at a large eye bank in Eastern India

    Directory of Open Access Journals (Sweden)

    Soham Basak

    2017-01-01

    Full Text Available Purpose: To compare the serology profile of donors from Hospital Cornea Retrieval Programme-donors (HCRP-D and voluntary cornea donors (VC-D from a large eye bank in Eastern India. Methods: This is a retrospective analysis of donor details from January 2011 to December 2016. Donor demographics, cause of death, and serology reports were compiled. Postmortem blood was tested for human immunodeficiency virus 1 and 2 (HIV, hepatitis B virus (HBV, hepatitis C virus (HCV, and syphilis using government-approved kits as per the National Programme for Control of Blindness Standards of Eye Banking. Donors for whom serology was not possible were excluded. Results: A total of 4300 of 4353 donors were included of which 74.3% were hospital donors and 25.7% were voluntary donors. A total of 93 (2.2% donors with 94 seropositive reports were noted: 79 (84.9% from HCRP-D and 14 (15.1% from VC-D which was statistically significantly higher (P = 0.02. Among seropositive reports, HIV, HBV, HCV, and syphilis accounted for 12 (12.8%, 38 (40.4%, 36 (38.3%, and eight (8.5%, respectively. There was no correlation between the cause of death and seropositivity. A statistically significant decreasing trend in seroprevalence among hospital donors was observed over the years (5.3% in 2011 to 1.4% in 2016; P = 0.004. Two (0.47% of 421 hospital donors with prior negative serology were found to be seropositive. Conclusion: Seropositive rates are significantly higher among hospital donors in spite of medical prescreening compared to nonscreened voluntary donors. Serology should be repeated even when prior reports are available.

  14. Cushing's Syndrome

    Science.gov (United States)

    Cushing's syndrome is a hormonal disorder. The cause is long-term exposure to too much cortisol, a hormone that ... your body to make too much cortisol. Cushing's syndrome is rare. Some symptoms are Upper body obesity ...

  15. Usher Syndrome

    Science.gov (United States)

    Usher syndrome is an inherited disease that causes serious hearing loss and retinitis pigmentosa, an eye disorder that causes ... and vision. There are three types of Usher syndrome: People with type I are deaf from birth ...

  16. Metabolic Syndrome

    Science.gov (United States)

    Metabolic syndrome is a group of conditions that put you at risk for heart disease and diabetes. These conditions ... agree on the definition or cause of metabolic syndrome. The cause might be insulin resistance. Insulin is ...

  17. Reye Syndrome

    Science.gov (United States)

    Reye syndrome is a rare illness that can affect the blood, liver, and brain of someone who has recently ... a viral illness, seek medical attention immediately. Reye syndrome can lead to a coma and brain death, ...

  18. Rett Syndrome

    Science.gov (United States)

    Rett syndrome is a rare genetic disease that causes developmental and nervous system problems, mostly in girls. It's related to autism spectrum disorder. Babies with Rett syndrome seem to grow and develop normally at first. ...

  19. Caplan syndrome

    Science.gov (United States)

    ... enable JavaScript. Rheumatoid pneumoconiosis (RP; also known as Caplan syndrome) is swelling (inflammation) and scarring of the ... avoid exposure to inorganic dust. Alternative Names RP; Caplan syndrome; Pneumoconiosis - rheumatoid; Silicosis - rheumatoid pneumoconiosis; Coal worker's ...

  20. Turner Syndrome

    Science.gov (United States)

    Turner syndrome is a genetic disorder that affects a girl's development. The cause is a missing or incomplete ... t work properly. Other physical features typical of Turner syndrome are Short, "webbed" neck with folds of skin ...

  1. Gardner's syndrome

    International Nuclear Information System (INIS)

    Sobrado Junior, C.W.; Bresser, A.; Cerri, G.G.; Habr-Gama, A.; Pinotti, H.W.; Magalhaes, A.

    1988-01-01

    A case of familiar poliposis of colon related to a right mandibular osteoma is reported (this association is usually called Gardner's syndrome). Radiologic pictures ae shown and some commentaries about this syndrome concerning the treatment are made. (author) [pt

  2. Sotos Syndrome

    Science.gov (United States)

    ... Clinical Trials Organizations Publications Definition Sotos syndrome (cerebral gigantism) is a rare genetic disorder caused by mutation ... have also been reported. × Definition Sotos syndrome (cerebral gigantism) is a rare genetic disorder caused by mutation ...

  3. Felty syndrome

    Science.gov (United States)

    Seropositive rheumatoid arthritis (RA); Felty's syndrome ... The cause of Felty syndrome is unknown. It is more common in people who have had rheumatoid arthritis (RA) for a long time. People with ...

  4. Bartter syndrome

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000308.htm Bartter syndrome To use the sharing features on this page, please enable JavaScript. Bartter syndrome is a group of rare conditions that affect ...

  5. Pendred Syndrome

    Science.gov (United States)

    ... other possible long-term consequences of the syndrome. Children with Pendred syndrome should start early treatment to gain communication skills, such as learning sign language or cued speech or learning to ...

  6. Dravet Syndrome

    Science.gov (United States)

    ... and supports a broad program of basic and clinical research on all types of epilepsy, including Dravet syndrome. Study of the genetic defects responsible for Dravet syndrome and related ... Publications Definition Dravet ...

  7. Uncertain Diagnosis of Fabry Disease in Patients with Neuropathic Pain, Angiokeratoma or Cornea Verticillata: Consensus on the Approach to Diagnosis and Follow-Up

    NARCIS (Netherlands)

    van der Tol, L.; Cassiman, David; Houge, Gunnar; Janssen, Mirian C.; Lachmann, Robin H.; Linthorst, Gabor E.; Ramaswami, Uma; Sommer, Claudia; Tøndel, Camilla; West, Michael L.; Weidemann, Frank; Wijburg, Frits A.; Svarstad, Einar; Hollak, Carla E. M.; Biegstraaten, Marieke

    2014-01-01

    Introduction: Individuals with neuropathic pain, angiokeratoma (AK) and/or cornea verticillata (CV) may be tested for Fabry disease (FD). Classical FD is characterised by a specific pattern of these features. When a patient presents with a non-specific pattern, the pathogenicity of a variant in the

  8. Uncertain diagnosis of fabry disease in patients with neuropathic pain, angiokeratoma or cornea verticillata: consensus on the approach to diagnosis and follow-up

    NARCIS (Netherlands)

    Tol, L. van der; Cassiman, D.; Houge, G.; Janssen, M.C.; Lachmann, R.H.; Linthorst, G.E.; Ramaswami, U.; Sommer, C.; Tondel, C.; West, M.L.; Weidemann, F.; Wijburg, F.A.; Svarstad, E.; Hollak, C.E.M.; Biegstraaten, M.

    2014-01-01

    INTRODUCTION: Individuals with neuropathic pain, angiokeratoma (AK) and/or cornea verticillata (CV) may be tested for Fabry disease (FD). Classical FD is characterised by a specific pattern of these features. When a patient presents with a non-specific pattern, the pathogenicity of a variant in the

  9. Establishment of a new in vitro test method for evaluation of eye irritancy using a reconstructed human corneal epithelial model, LabCyte CORNEA-MODEL.

    Science.gov (United States)

    Katoh, Masakazu; Hamajima, Fumiyasu; Ogasawara, Takahiro; Hata, Ken-ichiro

    2013-12-01

    Finding in vitro eye irritation testing alternatives to animal testing such as the Draize eye test, which uses rabbits, is essential from the standpoint of animal welfare. It has been developed a reconstructed human corneal epithelial model, the LabCyte CORNEA-MODEL, which has a representative corneal epithelium-like structure. Protocol optimization (pre-validation study) was examined in order to establish a new alternative method for eye irritancy evaluation with this model. From the results of the optimization experiments, the application periods for chemicals were set at 1min for liquid chemicals or 24h for solid chemicals, and the post-exposure incubation periods were set at 24h for liquids or zero for solids. If the viability was less than 50%, the chemical was judged to be an eye irritant. Sixty-one chemicals were applied in the optimized protocol using the LabCyte CORNEA-MODEL and these results were evaluated in correlation with in vivo results. The predictions of the optimized LabCyte CORNEA-MODEL eye irritation test methods were highly correlated with in vivo eye irritation (sensitivity 100%, specificity 80.0%, and accuracy 91.8%). These results suggest that the LabCyte CORNEA-MODEL eye irritation test could be useful as an alternative method to the Draize eye test. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Age-related changes in superoxide dismutase, glutathione peroxidase, catalase and xanthine oxidoreductase/xanthine oxidase activities in the rabbit cornea

    Czech Academy of Sciences Publication Activity Database

    Čejková, Jitka; Vejražka, M.; Pláteník, J.; Štípek, S.

    2004-01-01

    Roč. 39, - (2004), s. 1537-1543 ISSN 0531-5565 R&D Projects: GA ČR GA304/03/0419 Institutional research plan: CEZ:AV0Z5039906; CEZ:AV0Z5008914 Keywords : aging * cornea Subject RIV: FF - HEENT, Dentistry Impact factor: 2.880, year: 2004

  11. Irradiation of the rabbit cornea with UVB rays stimulates the expression of nitric oxide synthases-generated nitric oxide and the formation of cytotoxic nitrogen-related oxidants

    Czech Academy of Sciences Publication Activity Database

    Čejková, Jitka; Ardan, Taras; Andonova, Janetta; Zídek, Zdeněk

    2005-01-01

    Roč. 20, - (2005), s. 467-473 ISSN 0213-3911 R&D Projects: GA ČR GA304/03/0419 Institutional research plan: CEZ:AV0Z5008914 Keywords : UVB rays * Reactive nitrogen species * Cornea Subject RIV: FF - HEENT, Dentistry Impact factor: 2.023, year: 2005

  12. A Raman scattering and FT-IR spectroscopic study on the effect of the solar radiation in Antarctica on bovine cornea

    Science.gov (United States)

    Yamamoto, Tatsuyuki; Murakami, Naoki; Yoshikiyo, Keisuke; Takahashi, Tetsuya; Yamamoto, Naoyuki

    2010-01-01

    The Raman scattering and FT-IR spectra of the corneas, transported to the Syowa station in Antarctica and exposed to the solar radiation of the mid-summer for four weeks, were studied to reveal that type IV collagen involved in corneas were fragmented. The amide I and III Raman bands were observed at 1660 and 1245 cm -1, respectively, and the amide I and II infrared bands were observed at 1655 and 1545 cm -1, respectively, for original corneas before exposure. The background of Raman signals prominently increased and the ratio of amide II infrared band versus amide I decreased by the solar radiation in Antarctica. The control experiment using an artificial UV lamp was also performed in laboratory. The decline rate of the amide II/amide I was utilized for estimating the degree of fragmentation of collagen, to reveal that the addition of vitamin C suppressed the reaction while the addition of sugars promoted it. The effect of the solar radiation in Antarctica on the corneas was estimated as the same as the artificial UV lamp of four weeks (Raman) or one week (FT-IR) exposure.

  13. Down Syndrome

    Science.gov (United States)

    ... Down syndrome increases as a woman gets older. Down syndrome cannot be cured. Early treatment programs can help improve skills. They may include ... occupational, and/or educational therapy. With support and treatment, many ... Down syndrome live happy, productive lives. NIH: National Institute of ...

  14. Rowell syndrome

    Directory of Open Access Journals (Sweden)

    Ramesh Y Bhat

    2014-01-01

    Full Text Available Rowell syndrome is a rare disease consisting of erythema multiforme-like lesions associated with lupus erythematosus. The syndrome occurs mostly in middle-aged women. The authors describe the syndrome in a 15-year-old boy who responded well to systemic steroids and hydroxychloroquine.

  15. Aicardi Syndrome

    Science.gov (United States)

    ... from Aicardi-Goutieres syndrome, which is an inherited encephalopathy that affects newborn infants.) × Definition Aicardi syndrome is a rare genetic ... from Aicardi-Goutieres syndrome, which is an inherited encephalopathy that affects newborn infants.) View Full Definition Treatment There is no ...

  16. Characterization of a Multipeptide Lantibiotic Locus in Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Natalie Maricic

    2016-01-01

    Full Text Available Bacterial communities are established through a combination of cooperative and antagonistic interactions between the inhabitants. Competitive interactions often involve the production of antimicrobial substances, including bacteriocins, which are small antimicrobial peptides that target other community members. Despite the nearly ubiquitous presence of bacteriocin-encoding loci, inhibitory activity has been attributed to only a small fraction of gene clusters. In this study, we characterized a novel locus (the pld locus in the pathogen Streptococcus pneumoniae that drives the production of a bacteriocin called pneumolancidin, which has broad antimicrobial activity. The locus encodes an unusual tandem array of four inhibitory peptides, three of which are absolutely required for antibacterial activity. The three peptide sequences are similar but appear to play distinct roles in regulation and inhibition. A modification enzyme typically found in loci encoding a class of highly modified bacteriocins called lantibiotics was required for inhibitory activity. The production of pneumolancidin is controlled by a two-component regulatory system that is activated by the accumulation of modified peptides. The locus is located on a mobile element that has been found in many pneumococcal lineages, although not all elements carry the pld genes. Intriguingly, a minimal region containing only the genes required for pneumolancidin immunity was found in several Streptococcus mitis strains. The pneumolancidin-producing strain can inhibit nearly all pneumococci tested to date and provided a competitive advantage in vivo. These peptides not only represent a unique strategy for bacterial competition but also are an important resource to guide the development of new antimicrobials.

  17. 'Locus of control', health-related quality of life, emotional distress and disability in Parkinson's disease.

    Science.gov (United States)

    Rizza, Federica; Gison, Annalisa; Bonassi, Stefano; Dall'Armi, Valentina; Tonto, Francesca; Giaquinto, Salvatore

    2017-06-01

    This cross-sectional study evaluated locus of control and its subscales in Parkinson's disease. A total of 50 consecutive Parkinson's disease participants and 50 healthy volunteers (control group) were enrolled. External locus of control was significantly higher in Parkinson's disease participants, whereas internal locus of control had no significant differences. External locus of control and internal locus of control were correlated in control group, but not in Parkinson's disease. In Parkinson's disease participants, external locus of control was negatively associated with health-related quality of life as well as positively associated with emotional distress and disease severity (but not with disability). After adjusting to confound variables, the associations remained. On the other hand, internal locus of control was negatively associated with depression.

  18. The Effects of Locus of Control and Task Difficulty on Procrastination.

    Science.gov (United States)

    Janssen, Tracy; Carton, John S

    1999-12-01

    The authors investigated the effects of locus of control expectancies and task difficulty on procrastination. Forty-two college students were administered an academic locus of control scale and a task that was similar to a typical college homework assignment. The students were randomly assigned to 1 of 2 task difficulty levels. Although none of the results involving task difficulty was significant, several results involving locus of control were significant. Specifically, analyses revealed that students with internal locus of control expectancies tended to begin working on the assignment sooner than students with external locus of control expectancies. In addition, students with internal locus of control completed and returned the assignment sooner than students with external locus of control. The results are discussed within the context of J. B. Rotter's (1966, 1975, 1982) social learning theory.

  19. Common variants at SCN5A-SCN10A and HEY2 are associated with Brugada syndrome, a rare disease with high risk of sudden cardiac death

    DEFF Research Database (Denmark)

    Bezzina, Connie; Barc, Julien; Mizusawa, Yuka

    2013-01-01

    Brugada syndrome is a rare cardiac arrhythmia disorder, causally related to SCN5A mutations in around 20% of cases. Through a genome-wide association study of 312 individuals with Brugada syndrome and 1,115 controls, we detected 2 significant association signals at the SCN10A locus (rs10428132) a...

  20. Atomic force microscopy and transmission electron microscopy analyses of low-temperature laser welding of the cornea.

    Science.gov (United States)

    Matteini, Paolo; Sbrana, Francesca; Tiribilli, Bruno; Pini, Roberto

    2009-07-01

    Low-temperature laser welding of the cornea is a technique used to facilitate the closure of corneal cuts. The procedure consists of staining the wound with a chromophore (indocyanine green), followed by continuous wave irradiation with an 810 nm diode laser operated at low power densities (12-16 W/cm(2)), which induces local heating in the 55-65 degrees C range. In this study, we aimed to investigate the ultrastructural modifications in the extracellular matrix following laser welding of corneal wounds by means of atomic force microscopy and transmission electron microscopy. The results evidenced marked disorganization of the normal fibrillar assembly, although collagen appeared not to be denatured under the operating conditions we employed. The mechanism of low-temperature laser welding may be related to some structural modifications of the nonfibrillar extracellular components of the corneal stroma.

  1. Case report: a novel KERA mutation associated with cornea plana and its predicted effect on protein function

    DEFF Research Database (Denmark)

    Roos, Laura; Bertelsen, Birgitte; Harris, Pernille

    2015-01-01

    individuals, hypotrichosis was found. KERA was screened for mutations using Sanger sequencing. We detected a novel KERA variant, p.(Ile225Thr), that segregates with the disease in the homozygous form. The three-dimensional structure of keratocan protein was modelled, and we showed that this missense variation...... of the keratocan gene (KERA) on chromosome 12q22. To date, only nine different disease-associated KERA mutations, including four missense mutations, have been described. Case presentation: In this report, we present clinical data from a Turkish family with autosomal recessive cornea plana. In some of the affected...... are predicted to result in destabilization of the protein. Conclusion: We present the 10th pathogenic KERA mutation identified so far. Protein modelling is a useful tool in predicting the effect of missense mutations. This case underline the importance of the leucin rich repeat domain for the protein function...

  2. A comparative study of trabeculectomy and the new clear-cornea filtering procedure, intrastromal diathermal keratostomy (IDK)

    DEFF Research Database (Denmark)

    Bach-Holm, Daniella; Storr-Paulsen, Allan; Norregaard, Jens Christian

    2012-01-01

    Hg in the IDK group. The number of medications pre- and postoperatively in the trabeculectomy group was 3.1 and 0.5 versus 3.2 and 1.3 in the IDK group. Forty-four (59%) of the eyes in the trabeculectomy group met the complete success criteria compared with 5 (20%) in the IDK group (p......Purpose: For the first time to compare the 1-year success rates of trabeculectomy and the new clear-cornea filtering procedure, intrastromal diathermal keratostomy (IDK). Methods: Prospective clinical observational study including 99 consecutively operated eyes (69 patients) with well......-established primary open-angle glaucoma referred for filtering operation. We compared the change in intraocular pressure (IOP), number of anti-glaucomatous medication, complications and reoperations after 1 year. Seventy-four eyes were operated with trabeculectomy, and 25 with IDK. Complete success was defined as IOP...

  3. Collagen immobilized PVA hydrogel-hydroxyapatite composites prepared by kneading methods as a material for peripheral cuff of artificial cornea

    International Nuclear Information System (INIS)

    Kobayashi, Hisatoshi; Kato, Masabumi; Taguchi, Tetsushi; Ikoma, Toshiyuki; Miyashita, Hideyuki; Shimmura, Shigeto; Tsubota, Kazuo; Tanaka, Junzo

    2004-01-01

    In order to achieve the firm fixation of the artificial cornea to host tissues, composites of collagen-immobilized poly(vinyl alcohol) hydrogel with hydroxyapatite were synthesized by a hydroxyapatite particles kneading method. The preparation method, characterization, and the results of corneal cell adhesion and proliferation on the composite material were studied. PVA-COL-HAp composites were successfully synthesized. A micro-porous structure of the PVA-COL-HAp could be introduced by hydrochloric acid treatment and the porosity could be controlled by the pH of the hydrochloric acid solution, the treatment time, and the crystallinity of the HAp particles. Chick embryonic keratocyto-like cells were well attached and proliferated on the PVA-COL-HAp composites. This material showed potential for keratoprosthesis application. Further study such as a long-term animal study is now required

  4. One cornea for two patients: case report Uma córnea para dois pacientes: relato de caso

    Directory of Open Access Journals (Sweden)

    Ljubisa Nikolic

    2010-06-01

    Full Text Available Case reporting the use of one donor cornea for two transplantation procedures: deep anterior lamellar keratoplasty (DALK in a case of an imminent corneal perforation caused by herpetic stromal necrosis, and Descemet stripping with endothelial keratoplasty (DSEK in an eye with pseudophakic bullous keratopathy (PBK. Descemet's membrane (DM, denuded by stromal necrosis, served as the starting point for dissection plane and creation of the recipient bed for DALK. The next steps were excision of the diseased stroma along the edge of trephination, and transplantation of a 400-450 µm thick, manually dissected lamellar graft. The remaining posterior layers of the donor cornea, 100-150 µm thick, were used as a graft in the DSEK procedure for PBK. The integrity of the globe was saved, and best-corrected visual acuity (BCVA of 20/40 was reached after DALK in the eye with an imminent corneal perforation. A subnormal central corneal thickness (CCT of 430 µm did not interfere with corneal shape (43.50 x 45.50 D and function. The graft remained attached and clear after DSEK in the eye with PBK, with BCVA of 20/30 and a CCT of 653 µm. One donor cornea can be used for two lamellar keratoplasties, DALK and DSEK. Although the described obstacles may prevent this approach from becoming widely used, it may prove useful when one is confronted with a need for an urgent anterior lamellar keratoplasty, a long list of cases for DSEK, and a shortage of donor corneas.Relato de caso descrevendo o uso de uma córnea doadora para dois procedimentos de transplante: ceratoplastia anterior lamelar profunda (DALK no caso de uma perfuração corneal iminente causada por necrose estromal por herpes vírus, e ceratoplastia com transplante de endotélio (DSEK no olho com ceratopatia bolhosa em pseudofacia (PBK. A membrana de Descemet (DM, previamente desnudada pela necrose estromal, serviu como ponto de partida para o plano de dissecção e da criação do leito estromal para

  5. Scattered radiation dose to radiologist's cornea, thyroid and gonads while performing some x-ray fluoroscopic investigations

    International Nuclear Information System (INIS)

    Chougle, Arun

    1993-01-01

    The mankind has been immensely benefited from discovery of X-ray and it has found wide spread application in diagnosis and treatment. Radiation is harmful and can produce somatic and genetic effects in the exposed person. International Commission on Radiation Protection (ICRP) has recommended a system of dose limitation based on principle of ALARA. All the efforts should be made to keep the radiation dose to the radiation worker as low as possible. Fluoroscopy gives maximum dose to the patient and staff and hence we have attempted to quantify the scattered radiation dose to the cornea, thyroid and gonads of the radiologist performing fluoroscopic examinations such as barium meal, barium swallow, barium enema, myelography, histerosalpingography and fracture reduction. Thermoluminescence dosimetry (TLD) method using CaSO 4 :Dy TLD disc was employed for these measurements. Use of lead apron has reduced the dose to radiologist's gonad. (author). 3 refs., 4 tabs

  6. Genetic analysis of the claret locus of Drosophila melanogaster

    International Nuclear Information System (INIS)

    Sequeira, W.; Nelson, C.R.; Szauter, P.

    1989-01-01

    The claret (ca) locus of Drosophila melanogaster comprises two separately mutable domains, one responsible for eye color and one responsible for proper disjunction of chromosomes in meiosis and early cleavage divisions. Previously isolated alleles are of three types: (1) alleles of the claret (ca) type that affect eye color only, (2) alleles of the claret-nondisjunctional (ca nd ) type that affect eye color and chromosome behavior, and (3) a meiotic mutation, non-claret disjunctional (ncd), that affects chromosome behavior only. In order to investigate the genetic structure of the claret locus, the authors have isolated 19 radiation-induced alleles of claret on the basis of the eye color phenotype. Two of these 19 new alleles are of the ca nd type, while 17 are of the ca type, demonstrating that the two domains do not often act as a single target for mutagenesis. This suggests that the two separately mutable functions are likely to be encoded by separate or overlapping genes rather than by a single gene. One of the new alleles of the ca nd type is a chromosome rearrangement with a breakpoint at the position of the claret locus. If this breakpoint is the cause of the mutant phenotype and there are no other mutations associated with the rearrangement, the two functions must be encoded by overlapping genes

  7. Population genetics of the HRAS1 minisatellite locus

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, B.; Risch, N. (Yale Univ., New Haven, CT (United States)); Krontiris, T. (Tufts Univ., Boston, MA (United States) New England Medical Center Hospital, Boston, MA (United States))

    1993-12-01

    Several years ago it was reported that rare HRAS1 VNTR alleles occurred more frequently in US Caucasian cancer patients than in unaffected controls. Such an association, in theory, could be caused by undetected population heterogeneity. Also, in a study clearly relevant to this issue, it was recently reported that significant deviations from Hardy-Weinberg equilibrium exist at this locus in a sample of US Caucasians. These considerations motivate population genetic analysis of the HRAS1 locus. From published studies of the HRAS1 VNTR locus, which classified alleles into types, the authors found only small differences in the allele frequency distributions of samples from various European nations, although there were larger differences among ethnic groups (African American, Caucasian, and Oriental). In an analysis of variation of rare-allele frequencies among samples from four European nations, most of the variance was attributable to molecular methodology, and very little of the variance was accounted for by nationality. In addition, the authors showed that mixture of European subpopulations should result in only minor deviations from expected genotype proportions in a Caucasian database and demonstrated that there was no significant deviation from Hardy-Weinberg equilibrium in the HRAS1 data. 35 refs., 4 tabs.

  8. Origin of allelic diversity in antirrhinum S locus RNases.

    Science.gov (United States)

    Xue, Y; Carpenter, R; Dickinson, H G; Coen, E S

    1996-01-01

    In many plant species, self-incompatibility (SI) is genetically controlled by a single multiallelic S locus. Previous analysis of S alleles in the Solanaceae, in which S locus ribonucleases (S RNases) are responsible for stylar expression of SI, has demonstrated that allelic diversity predated speciation within this family. To understand how allelic diversity has evolved, we investigated the molecular basis of gametophytic SI in Antirrhinum, a member of the Scrophulariaceae, which is closely related to the Solanaceae. We have characterized three Antirrhinum cDNAs encoding polypeptides homologous to S RNases and shown that they are encoded by genes at the S locus. RNA in situ hybridization revealed that the Antirrhinum S RNase are primarily expressed in the stylar transmitting tissue. This expression is consistent with their proposed role in arresting the growth of self-pollen tubes. S alleles from the Scrophulariaceae form a separate group from those of the Solanaceae, indicating that new S alleles have been generated since these families separated (approximately 40 million years). We propose that the recruitment of an ancestral RNase gene into SI occurred during an early stage of angiosperm evolution and that, since that time, new alleles subsequently have arisen at a low rate. PMID:8672882

  9. Quantification of small fiber pathology in patients with sarcoidosis and chronic pain using cornea confocal microscopy and skin biopsies

    Directory of Open Access Journals (Sweden)

    Oudejans LCJ

    2017-08-01

    Full Text Available Linda CJ Oudejans,1 Marieke Niesters,1 Michael Brines,2 Albert Dahan,1 Monique van Velzen1 1Department of Anesthesiology, Leiden University Medical Center, Leiden, the Netherlands; 2Araim Pharmaceuticals, Inc., Tarrytown, NY, USA Abstract: Small fiber pathology with concomitant chronic neuropathic pain is a common complication of sarcoidosis. The gold standard of diagnosis of small fiber neuropathy (SFN is the quantification of small nerve fibers in skin biopsies in combination with patient history and psychophysical tests; a new technique is the quantification of small nerve fibers in the cornea using cornea confocal microscopy (CCM. Here, we studied small fiber morphology in sarcoidosis patients with neuropathic pain using skin biopsies, CCM, and quantitative sensory testing (QST. Our aim was to construct specific phenotypes of neuropathic pain in sarcoidosis. Fifty-eight patients with a confirmed diagnosis of sarcoidosis and with moderate-to-severe neuropathic pain were tested. Decreased intraepidermal nerve fiber density (IENFD from skin biopsies was found in 28% of patients, and CCM abnormalities were observed in 45% of patients. There was no correlation between CCM and IENFD abnormalities. Eighty-three percent of patients had abnormal thermal detection thresholds, a sign of small fiber dysfunction. Based on the presence or absence of abnormalities in IENFD and CCM, four distinct phenotypes were identified with a distinct homogeneous pattern of somatosensory symptoms. We argue that these distinct phenotypes have a similar mechanistic construct with specific phenotype-specific treatment options. Additionally, our data suggest the presence of patients with length- and nonlength-dependent SFN within this population of sarcoidosis patients. Keywords: chronic pain, sarcoidosis, small fiber neuropathy

  10. The improvement of dry eye after cataract surgery by intraoperative using ophthalmic viscosurgical devices on the surface of cornea

    Science.gov (United States)

    He, Yuan; Li, Jia; Zhu, Jingfen; Jie, Ying; Wang, Ningli; Wang, Jun

    2017-01-01

    Abstract Backgroud: This study aimed to investigate the protective effect of intraoperative used hydroxypropyl methylcellulose (HPMC 2%) on the ocular surface after cataract surgery. Methods: A total of 149 eyes (149 patients) diagnosed with age-related cataract, age 69.19 ± 9.74 years, were enrolled in this prospective, parallel-design, continuous, randomised controlled study. Patients were randomly assigned to receive HPMC 2% (study group) or balanced salt solution (control group) during the surgery to moisturize the cornea surface. The Ocular Surface Disease Index, Schirmer test without topical anesthetics, tear break-up time, and corneal fluorescein staining were assessed preoperatively, 1 day, 1 week, and 1 month after the surgery, respectively. Results: The Schirmer test value of male patients in the study group at 1 week postoperation was higher than that of male patients in the control group (P = .019). For patients diagnosed with dry eye before the surgery, Schirmer test value in the male patients in the study group at 1 month after surgery was higher than that in the male patients in the control group (P = .037). Furthermore, for the cluster of preoperative dry eye patients whose surgical time was longer than median, corneal fluorescein staining of the patients in the study group was superior to that of the patients in the control group (P = .032). Conclusion: Intraoperative use of HPMC 2% on the cornea surface could improve clinical outcomes of tear film and ocular surface health to some degree, especially in the patients diagnosed with dry eye before the surgery, male patients, and patients whose surgical time was relatively longer. PMID:29390284

  11. New intraocular pressure measurement method using reflected pneumatic pressure from cornea deformed by air puff of ring-type nozzle.

    Science.gov (United States)

    Kim, Hyung Jin; Seo, Yeong Ho; Kim, Byeong Hee

    2017-01-01

    In this study, a non-contact type intraocular pressure (IOP) measuring system using reflected pneumatic pressure is proposed to overcome the disadvantages of existing measurement systems. A ring-type nozzle, a key component in the proposed system, is designed via computational fluid analysis. It predicts the reflected pneumatic pressure based on the nozzle exit angle and inner and outer diameters of the nozzle, which are 30°, 7 mm, and 9 mm, respectively. Performance evaluation is conducted using artificial eyes fabricated using polydimethylsiloxane with the specifications of human eyes. The IOP of the fabricated artificial eyes is adjusted to 10, 30, and 50 mm Hg, and the reflected pneumatic pressure is measured as a function of the distance between the ring-type nozzle and artificial eye. The measured reflected pneumatic pressure is high when the measurement distance is short and eye pressure is low. The cornea of an artificial eye is significantly deformed at a low IOP, and the applied pneumatic pressure is more concentrated in front of the ring-type nozzle because of the deformed cornea. Thus, the reflected pneumatic pressure at a low IOP has more inflows into the pressure sensor inserted inside the nozzle. The sensitivity of the output based on the IOP at measurement distances between 3-5 mm is -0.0027, -0.0022, -0.0018, -0.0015, and -0.0012. Sensitivity decreases as the measurement distance increases. In addition, the reflected pneumatic pressure owing to the misalignment at the measurement distances of 3-5 mm is not affected within a range of 0.5 mm. Therefore, the measurement range is acceptable up to a 1 mm diameter from the center of an artificial eye. However, the accuracy gradually decreases as the reflected pneumatic pressure from a misalignment of 1 mm or more decreases by 26% or more.

  12. Changes in mechanical, chemical, and thermal sensitivity of the cornea after topical application of nonsteroidal anti-inflammatory drugs.

    Science.gov (United States)

    Acosta, M Carmen; Berenguer-Ruiz, Leticia; García-Gálvez, Alberto; Perea-Tortosa, David; Gallar, Juana; Belmonte, Carlos

    2005-01-01

    In addition to their well-known anti-inflammatory actions, some of the nonsteroidal anti-inflammatory drugs (NSAIDs) appear to have an analgesic effect. In human subjects, the changes in threshold and intensity of sensations evoked by mechanical, chemical, and thermal stimulation of the cornea induced by topical administration of two commercial NSAIDs, diclofenac sodium (Voltaren; Novartis, Basel, Switzerland) and flurbiprofen (Ocuflur; Allergan, Irvine, CA), were studied. Corneal sensitivity was measured in 10 young, healthy subjects with a gas esthesiometer. Chemical (10%-70% CO2 in air), mechanical (0-264 mL/min), and thermal (corneal temperature changes between -4.5 degrees C and +3 degrees C around the normal value) stimuli were applied to the center of the cornea. The intensity and perceived magnitude of the psychophysical attributes of the evoked sensation were scored at the end of the pulse in a 10-cm, continuous visual analog scale (VAS). The threshold was expressed as the stimulus intensity that evoked a VAS score >0.5. Sensitivity was measured in both eyes of each subject on two separate days, one without treatment and the other 30 minutes after topical application of 0.03% flurbiprofen (seven subjects) or 0.1% diclofenac sodium (six subjects). Diclofenac attenuated significantly all the sensation parameters evoked by high-intensity mechanical, chemical, and thermal stimuli. Flurbiprofen produced a slight reduction of the sensations evoked by mechanical and chemical stimulation that became significant only for the irritation caused by chemical stimuli of maximum intensity (70% CO2). None of the drugs modified significantly the detection threshold of the different stimuli. Flurbiprofen had a very limited effect on sensations evoked by corneal stimulation, whereas diclofenac reduced the intensity of sensations evoked by stimuli of different modality, suggesting a mild local anesthetic effect of this drug on all types of corneal sensory fibers. Such

  13. Surgical peripheral iridectomy via a clear-cornea phacoemulsification incision for pupillary block following cataract surgery in acute angle closure.

    Science.gov (United States)

    Fang, Aiwu; Wang, Peijuan; He, Rui; Qu, Jia

    2018-05-18

    To describe a technique of surgical peripheral iridectomy via a clear-cornea tunnel incision to prevent or treat pupillary block following phacoemulsification. Description of technique and retrospective description results in 20 eyes of 20 patients with acute angle closure with coexisting visually significant cataract undergoing phacoemulsification considered at risk of postoperative papillary block as well as two pseudo-phakic eyes with acute postoperative pupillary-block. Following phacoemulsification and insertion of an intraocular lens, a needle with a bent tip was inserted behind the iris through the corneal tunnel incision. A blunt iris repositor was introduced through the paracentesis and placed above the iris to exert posterior pressure and create a puncture. The size of the puncture was enlarged using scissors. For postoperative pupillary block the same technique was carried out through the existing incisions created for phacoemulsification. Peripheral iridectomy was successfully created in all 22 eyes. At a mean follow-up of 18.77 ± 9.72 months, none of the iridectomies closed or required enlargement. Two eyes had mild intraoperative bleeding and one eye a small Descemet's detachment that did not require intervention. No clinically significant complications were observed. Visual acuity and IOP improved or was maintained in all patients. The incidence of pupillary block in our hospital was 0.09% overall, 0.6% in diabetics and 3.5% in those with diabetic retinopathy. This technique of peripheral iridectomy via the cornea tunnel incision can be safely used during phacoemulsification in eyes at high risk of pupillary block or in the treatment of acute postoperative pupillary-block after cataract surgery. The technique is likely to be especially useful in brown iris, or if a laser is not available.

  14. High-resolution mapping of the x-linked hypohidrotic ectodermal dysplasia (EDA) locus

    Energy Technology Data Exchange (ETDEWEB)

    Zonana, J.; Jones, M.; Litt, M.; Kramer, P.; Browne, D.; Becker, H.W. (Oregon Health Sciences Univ., Portland, OR (United States)); Brockdorff, N.; Rastan, S. (Medical Council Clinical Research Centre, Harrow (United Kingdom)); Davies, K.P.; Clarke, A. (Univ. of Wales College of Medicine, Cardiff (United Kingdom)) (and others)

    1992-11-01

    The X-linked hypohidrotic ectodermal dysplasia (EDA) locus has been previously localized to the subchromosomal region Xq11-q21.1. The authors have extended previous linkage studies and analyzed linkage between the EDA locus and 10 marker loci, including five new loci, in 41 families. Four of the marker loci showed no recombination with the EDA locus, and six other loci were also linked to the EDA locus with recombination fractions of .009-.075. Multipoint analysis gave support to the placement of the PGK1P1 locus proximal to the EDA locus and the DXS453 and PGK1 loci distal to EDA. Further ordering of the loci could be inferred from a human-rodent somatic cell hybrid derived from an affected female with EDA and an X;9 translocation and from studies of an affected male with EDA and a submicroscopic deletion. Three of the proximal marker loci, which showed no recombination with the EDA locus, when used in combination, were informative in 92% of females. The closely linked flanking polymorphic loci DXS339 and DXS453 had heterozygosites of 72% and 76%, respectively, and when used jointly, they were doubly informative in 52% of females. The human DXS732 locus was defined by a conserved mouse probe pcos169E/4 (DXCrc169 locus) that consegregates with the mouse tabby (Ta) locus, a potential homologue to the EDA locus. The absence of recombination between EDA and the DXSA732 locus lends support to the hypothesis that the DXCrc169 locus in the mouse and the DXS732 locus in humans may contain candidate sequences for the Ta and EDA genes, respectively. 36 refs., 1 fig., 5 tabs.

  15. Determination of natamycin in rabbit cornea by high-performance liquid chromatography-tandem mass spectrometry with protective soaking extraction technology.

    Science.gov (United States)

    Tianyang, Zhou; Ling, Zhu; Huiyun, Xia; Jijun, He; Junjie, Zhang

    2014-10-15

    A new selective and sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the quantification of natamycin (NAT) in rabbit corneas with amphotericin B as the internal standard (IS). The cornea samples were processed by a simple and protective methanol soaking extraction technology. The NAT could be extracted completely from rabbit cornea after 24h of soaking with methanol under a mild condition. Chromatographic separation was performed on a C18 column (2.1mm×50mm, 3.5μm) using mobile phase with ammonium acetate buffer (pH 4.5; 4.0mM):acetonitrile (40:60, v/v) at a flow rate of 0.25ml/min. Quantification was performed using the transitions 666.2→503.2 m/z for NAT and 924.5→906.6 m/z for IS by positive ion electrospray ionization in multiple reaction monitoring mode. The assay was validated over a concentration range of 8.64ng/ml to 843ng/ml with lower limit of detection of 4.32ng/ml. The method was validated with respect to linearity, accuracy, precision, recovery, stability and extracting efficiency. The extraction recovery of NAT from cornea samples was approximately 100% with the new methanol soaking extraction procedure. The method has been successfully applied to the ocular pharmacokinetic studies of NAT eye drops in the cornea of Japanese white rabbit. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Dravets syndrom

    DEFF Research Database (Denmark)

    Hansen, Lars Kjaersgård; Rasmussen, Niels Henrik; Ousager, Lilian Bomme

    2010-01-01

    Dravet syndrome is an epileptic syndrome of infancy and early childhood. Most cases of Dravet syndrome seem to be due to a genetic defect causing the sodium channel to malfunction. We describe the main features of the syndrome. This epilepsy is medically intractable, but we call attention...... to the fact that some medications are of benefit and some could exacerbate the condition. Early recognition of the syndrome including by genetic testing could possibly improve outcome and reduce the need for other specialized investigations. Udgivelsesdato: 2010-Feb-22...

  17. Locus de Controle e escolha do método anticoncepcional Locus de Control y método anticonceptivo elegido Locus of Control and choice of contraceptive method

    Directory of Open Access Journals (Sweden)

    Aline Salheb Alves

    2007-06-01

    Full Text Available Objetivou-se avaliar a relação entre o Locus de Controle e o tipo de método contraceptivo escolhido. Foi utilizada a Escala Multidimensional de Locus de Controle de Levenson e entrevistadas 191 mulheres. As usuárias de preservativo masculino apresentaram maior Internalidade do que as usuárias de injetável mensal. Quanto ao locus Externalidade Outros Poderosos, as usuárias de implante apresentavam menor externalidade do que as usuárias de preservativo masculino, laqueadura, injetável trimestral e DIU. Considerando-se o locus Externalidade Acaso, as usuárias de implante apresentaram menores escores do que as mulheres que optaram pela laqueadura, injetável trimestral e DIU. Observou-se ainda, menor Externalidade Acaso entre as usuárias de injetável mensal em relação às mulheres que fizeram opção pelo injetável trimestral.El objetivo es validar la relación entre el Locus de Control y el tipo de método anticonceptivo elegido. Fue usada la Escala Multidimensional de Locus de Control de Levenson. Fueron entrevistadas 191 mujeres. Las usuarias de condón masculino presentaron Internalidad más grande que las usuarias de inyectable mensual. Considerado el Locus Externalidad - Otro poderoso, las usuarias de implante presentaron menor externalidad de que las usuarias de condón masculino, laqueadura, inyectable trimestral y DIU. Considerado el Locus Externalidad - Quizá, las usuarias del implante presentaron menores resultados que las mujeres que eligieron por la laqueadura, inyectable trimestral y DIU. Se observo que las mujeres usuarias de inyectable mensual presentaron menor Externalidad - Quizá que las mujeres usuarias de inyectable trimestral.The purpose was to assess the relationship between locus of control and the contraceptive method chosen. It was used the Levenson's Multidimensional Locus of Control Scale and 191 women was interviewed. Users of male condoms presented greater Internality than the monthly contraceptive

  18. Refinement of the NHS locus on chromosome Xp22.13 and analysis of five candidate genes.

    Science.gov (United States)

    Toutain, Annick; Dessay, Benoît; Ronce, Nathalie; Ferrante, Maria-Immacolata; Tranchemontagne, Julie; Newbury-Ecob, Ruth; Wallgren-Pettersson, Carina; Burn, John; Kaplan, Josseline; Rossi, Annick; Russo, Silvia; Walpole, Ian; Hartsfield, James K; Oyen, Nina; Nemeth, Andrea; Bitoun, Pierre; Trump, Dorothy; Moraine, Claude; Franco, Brunella

    2002-09-01

    Nance-Horan syndrome (NHS) is an X-linked condition characterised by congenital cataracts, dental abnormalities, dysmorphic features, and mental retardation in some cases. Previous studies have mapped the disease gene to a 2 cM interval on Xp22.2 between DXS43 and DXS999. We report additional linkage data resulting from the analysis of eleven independent NHS families. A maximum lod score of 9.94 (theta=0.00) was obtained at the RS1 locus and a recombination with locus DXS1195 on the telomeric side was observed in two families, thus refining the location of the gene to an interval of around 1 Mb on Xp22.13. Direct sequencing or SSCP analysis of the coding exons of five genes (SCML1, SCML2, STK9, RS1 and PPEF1), considered as candidate genes on the basis of their location in the critical interval, failed to detect any mutation in 12 unrelated NHS patients, thus making it highly unlikely that these genes are implicated in NHS.

  19. Mutation in PLK4, encoding a master regulator of centriole formation, defines a novel locus for primordial dwarfism.

    Science.gov (United States)

    Shaheen, Ranad; Al Tala, Saeed; Almoisheer, Agaadir; Alkuraya, Fowzan S

    2014-12-01

    Primordial dwarfism (PD) is a heterogeneous clinical entity characterised by severe prenatal and postnatal growth deficiency. Despite the recent wave of disease gene discovery, the causal mutations in many PD patients remain unknown. To describe a PD family that maps to a novel locus. Clinical, imaging and laboratory phenotyping of a new family with PD followed by autozygosity mapping, linkage analysis and candidate gene sequencing. We describe a multiplex consanguineous Saudi family in which two full siblings and one half-sibling presented with classical features of Seckel syndrome in addition to optic nerve hypoplasia. We were able to map the phenotype to a single novel locus on 4q25-q28.2, in which we identified a five base-pair deletion in PLK4, which encodes a master regulator of centriole duplication. Our discovery further confirms the role of genes involved in centriole biology in the pathogenesis of PD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  20. The Locus Preservation Hypothesis: Shared Linguistic Profiles across Developmental Disorders and the Resilient Part of the Human Language Faculty

    Directory of Open Access Journals (Sweden)

    Evelina Leivada

    2017-10-01

    Full Text Available Grammatical markers are not uniformly impaired across speakers of different languages, even when speakers share a diagnosis and the marker in question is grammaticalized in a similar way in these languages. The aim of this work is to demarcate, from a cross-linguistic perspective, the linguistic phenotype of three genetically heterogeneous developmental disorders: specific language impairment, Down syndrome, and autism spectrum disorder. After a systematic review of linguistic profiles targeting mainly English-, Greek-, Catalan-, and Spanish-speaking populations with developmental disorders (n = 880, shared loci of impairment are identified and certain domains of grammar are shown to be more vulnerable than others. The distribution of impaired loci is captured by the Locus Preservation Hypothesis which suggests that specific parts of the language faculty are immune to impairment across developmental disorders. Through the Locus Preservation Hypothesis, a classical chicken and egg question can be addressed: Do poor conceptual resources and memory limitations result in an atypical grammar or does a grammatical breakdown lead to conceptual and memory limitations? Overall, certain morphological markers reveal themselves as highly susceptible to impairment, while syntactic operations are preserved, granting support to the first scenario. The origin of resilient syntax is explained from a phylogenetic perspective in connection to the “syntax-before-phonology” hypothesis.

  1. Psychometric properties of the multidimensional health locus of control scale form C in a non-Western culture.

    Directory of Open Access Journals (Sweden)

    Barna Konkolÿ Thege

    Full Text Available Form C of the Multidimensional Health Locus of Control Scales (MHLC-C was designed to investigate health-related control beliefs of persons with an existing medical condition. The aim of the present study was to examine the psychometric properties of this instrument in a culture characterized by external control beliefs and learned helplessness-contrary to the societal context of original test development. Altogether, 374 Hungarian patients with cancer, irritable bowel syndrome, diabetes, and cardiovascular and musculoskeletal disorders were enrolled in the study. Besides the MHLC-C, instruments measuring general control beliefs, anxiety, depression, self-efficacy, and health behaviors were also administered to evaluate the validity of the scale. Both exploratory and confirmatory factor analytic techniques were used to investigate the factor structure of the scale. Our results showed that the Hungarian adaptation of the instrument had a slightly different structure than the one originally hypothesized: in the present sample, a three-factor structure emerged where the items of the Doctors and the Others subscales loaded onto a single common component. Internal reliability of all three subscales was adequate (alphas between .71 and .79. Data concerning the instrument's validity were comparable with previous results from Western countries. These findings may suggest that health locus of control can be construed very similarly to Western countries even in a post-communist society-regardless of the potential differences in general control beliefs.

  2. Examining the relationship between health locus of control and God Locus of Health Control: Is God an internal or external source?

    Science.gov (United States)

    Boyd, Joni M; Wilcox, Sara

    2017-11-01

    For many people, the influence of believing in a higher power can elicit powerful effects. This study examined the relationship between God control, health locus of control, and frequency of religious attendance within 838 college students through online surveys. Regression analysis showed that chance and external locus of control and frequency of religious attendance were significant and positive predictors of God Locus of Health Control. The association of powerful others external locus of control and God Locus of Health Control differed by race (stronger in non-Whites than Whites) and somewhat by gender (stronger in women than men). For some people, the role of a supreme being, or God, should be considered when designing programs for improving health behaviors.

  3. Association between alleles of the transforming growth factor alpha locus and cleft lip and palate in the Chilean population

    Energy Technology Data Exchange (ETDEWEB)

    Jara, L.; Blanco, R.; Chiffelle, I. [Univ. of Chile, Santiago (Chile)] [and others

    1995-07-17

    Two RFLPs at the TGFA locus were studied in 39 unrelated Chilean (Caucasoid-Mongoloid) patients with non-syndromic cleft lip/palate [CL(P)] and 51 control individuals. A highly significant association between BamHI A2 allele and CL(P) was detected ({chi}{sub 2} = 6.00; P = 0.014), while no association was found between TaqI RFLPs and clefting. No significant differences were found when comparing genotypes by type of cleft and a positive or negative family history of clefting. Our results seem to support rather definitively the association between TGFA and clefting but not support the hypothesis that TGFA is a major causal gene of CL(P). 29 refs., 5 tabs.

  4. HEALTH LOCUS OF CONTROL PERCEPTION OF ADOLESCENTS, AND ITS EFFECTS ON THEIR HEALTH BEHAVIOURS

    Directory of Open Access Journals (Sweden)

    Ruhi Selcuk TABAK

    2006-04-01

    Full Text Available Main objective of this study is to investigate the relationships between health locus of control perceptions and health behaviours of adolescents as well as the effectiveness of lectures on health locus of control to them. The subjects of our study are 192 students in 6 groups of the 9. Grade students of a high school. Three groups of 108 students were randomly selected as the experiment group who were subjected to 4 class-hours specific lectures on health locus of control. The rest 84 students constituted the control group. A 34-item questionnaire for health behaviours and the Multidimensional Health Locus of Control Scale (MHLOC, were filled by the students before and after the lectures. The lectures on health locus of control increased the perception of internal health locus of control of adolescents while decreasing chance health locus of control. The differences between experiment and control groups in this aspect were found to be statistically significant. Internal health locus of control is the main source for the increase of responsibility and management of individuals on their health. The relations that were detected between students’ health behaviours and information solicitation and their perceptions of health locus of control showed that the students with higher internal health locus of control are more eager to be responsible and active for their health, especially, for the health behaviours such as physical exercise, smoking, tooth-brushing, medical check-ups so on. [TAF Prev Med Bull 2006; 5(2.000: 118-130

  5. In vivo genome editing of the albumin locus as a platform for protein replacement therapy

    Science.gov (United States)

    Sharma, Rajiv; Anguela, Xavier M.; Doyon, Yannick; Wechsler, Thomas; DeKelver, Russell C.; Sproul, Scott; Paschon, David E.; Miller, Jeffrey C.; Davidson, Robert J.; Shivak, David; Zhou, Shangzhen; Rieders, Julianne; Gregory, Philip D.; Holmes, Michael C.; Rebar, Edward J.

    2015-01-01

    Site-specific genome editing provides a promising approach for achieving long-term, stable therapeutic gene expression. Genome editing has been successfully applied in a variety of preclinical models, generally focused on targeting the diseased locus itself; however, limited targeting efficiency or insufficient expression from the endogenous promoter may impede the translation of these approaches, particularly if the desired editing event does not confer a selective growth advantage. Here we report a general strategy for liver-directed protein replacement therapies that addresses these issues: zinc finger nuclease (ZFN) –mediated site-specific integration of therapeutic transgenes within the albumin gene. By using adeno-associated viral (AAV) vector delivery in vivo, we achieved long-term expression of human factors VIII and IX (hFVIII and hFIX) in mouse models of hemophilia A and B at therapeutic levels. By using the same targeting reagents in wild-type mice, lysosomal enzymes were expressed that are deficient in Fabry and Gaucher diseases and in Hurler and Hunter syndromes. The establishment of a universal nuclease-based platform for secreted protein production would represent a critical advance in the development of safe, permanent, and functional cures for diverse genetic and nongenetic diseases. PMID:26297739

  6. Hitch-hiking from HRAS1 to the WAGR locus with CMGT markers

    Energy Technology Data Exchange (ETDEWEB)

    Bickmore, W.; Christie, S.; van Heyningen, V.; Hastie, N.D.; Porteous, D.J.

    1988-01-11

    The clinical association of Wilms' tumor with aniridia, genitourinary abnormalities and mental retardation (WAGR syndrome) is characterized cytogenetically by variable length, constitutional deletion of the short arm of chromosome 11, which always includes at least part of band 11p13. HRAS1-selected chromosome mediated gene transfer (CMGT) generated a transformant, E65-6, in which the only human genes retained map either to band 11p13 or, with HRAS1, in the region 11p15.4-pter. Human recombinants isolated from E65-6 were mapped to a panel of five WAGR deletion hybrids and two clinically related translocations. The authors show that E65-6 is enriched -400-fold for 11p15.4-pter markers and -200-fold for 11p13 markers. Hitch-hiking from HRAS1 with CMGT markers has allowed us to define seven discrete intervals which subtend band 11p13. Both associated translocations co-locate within the smallest region of overlap with the WAGR locus, which has been redefined by identifying a new interval closer than FSHB.

  7. Germ-line mutations at a mouse ESTR (Pc-3) locus and human microsatellite loci

    International Nuclear Information System (INIS)

    Ryo, Haruko; Nakajima, Hiroo; Nomura, Taisei

    2006-01-01

    We examined the use of the mouse Pc-3 ESTR (expanded simple tandem repeat) locus and 72 human microsatellite loci as potentially sensitive biomarkers for mutagenic exposures to germ cells in mice and humans respectively. In the mouse work, we treated male mice with TCDD (2, 3, 7, 8-tetrachlo-rodibenzo-p-dioxin; a chemical known to induce congenital anomalies in humans and mice) and, analysed the F 1 fetuses for Pc-3 mutations. Although the incidence of anomalies was higher in the TCDD group, there were no induced mutations. However, respiratory distress syndrome (RDS) was observed in 3 of 7 fetuses born to male mice which were treated with TCDD and which showed abnormal length of Pc-3 allele. In the human studies, the children of Chernobyl liquidators were examined for mutations at a total of 72 (31 autosomal, 1 X-linked and 40 Y-linked) microsatellite loci. This study was prompted by earlier findings of increases in microsatellite mutations in barn swallows and wheat in the highly contaminated areas after the Chernobyl accident. We examined 64 liquidator families (70 children) and 66 control families (70 children). However, no increases in mutation rates were found. The estimated mean dose to the liquidators was about 39 mSv and this might be one possible reason why no increases of mutations could be found. (author)

  8. Biophysico-functional compatibility of Seoul National University (SNU) miniature pig cornea as xenocorneal graft for the use of human clinical trial.

    Science.gov (United States)

    Kim, Dong Hyun; Kim, Jaeyoung; Jeong, Hyun Jeong; Lee, Hyun Ju; Kim, Mee Kum; Wee, Won Ryang

    2016-05-01

    Xenocorneal transplantation is one of the solutions for shortage of donor cornea, and remarkable advances have been made in pig-to-rhesus studies from the immunological perspective. Most successful preclinical trials have been carried out with corneas of the Seoul National University (SNU) miniature pig (SNU pig, genetically unmodified) as donor tissues; however, there has been no biophysico-functional evaluation of the SNU pig cornea as a substitute for human cornea. The purpose of this study was to investigate the biophysical and functional compatibility of SNU pig cornea for use in human clinical trials. Ninety-three eyeballs obtained from 51 SNU pigs were used to evaluate the physical properties and changes in porcine corneal endothelial cells (PCECs) depending on preservation time and storage condition before surgery, proliferative and functional characteristics of PCECs, and the microbiologic safety of porcine cornea. Corneal diameters and curvatures, axial length, anterior chamber depth, and central corneal thickness were measured and compared with previously reported human data. Corneal endothelial cell density (ECD) was serially measured with a confocal microscope during 7 days of preservation in the same storage solution used for human corneas. Corneal endothelial cell proliferation and immunofluorescence staining of Na- and K-dependent ATPase in PCECs were evaluated after 7 days of preservation. The corneoscleral rims of SNU pigs were cultured for gram-positive bacteria, gram-negative bacteria, and fungi to evaluate their microbiological safety. Corneal diameter and thickness in SNU pigs was larger than human and corneal curvature was flatter; however, they were within surgically operable ranges. Mean ECD (day 0) and ECD loss after 7 days of preservation were 2625 ± 81 cells/mm(2) and 7.60 ± 1.53%, respectively, which is comparable to human ECD and ECD loss in the same conditions. The ECD of SNU pigs was inversely decreased with aging (R(2) = 0.4034, P

  9. Mucous membrane grafting for the post-Steven-Johnson syndrome symblepharon: A case report

    Directory of Open Access Journals (Sweden)

    Jayanta Kumar Das

    2011-01-01

    Full Text Available An 18-year-old woman was referred with late sequelae of chloroquine-induced Steven-Johnson syndrome. At the time of presentation, the symblepharon was involving the upper lids to almost the whole of the cornea, and part of the lower bulbar conjunctiva with the lower lid bilaterally. Other ocular examinations were not possible due to the symblepharon. B-scan ultrasonography revealed acoustically clear vitreous, normal chorioretinal thickness, and normal optic nerve head, with an attached retina. Conjunctivo-corneal adhesion released by superficial lamellar dissection of the cornea. Ocular surface reconstruction was carried out with a buccal mucous membrane. A bandage contact lens was placed over the cornea followed by the symblepharon ring to prevent further adhesion. The mucosal graft was well taken up along with corneal re-epithelization. Best corrected visual acuity of 20/120 in both sides after 1 month and 20/80 after 3 months was achieved and maintained till the 2.5-year follow-up.

  10. A Case of Bardet-Biedl Syndrome

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    katayon Etemadi

    2007-09-01

    Full Text Available Etemadi K1, Khazaii MR2 1. MSC of Human Genetic, Molecular Medicine and Genetic department, Medical school, Hamadan University of medical sciences. 2. Assistant professor of Pediatric Urology Abstract Background: The Bardet Biedl syndrome is a heterogenous and autosomal recessive disorder. Primary features are: retinitis pigmentosa, obesity, polydactyly, mental retardation, renal abnormalities and hypogonadism. Renal failure is the major cause of death in homozygote patients, with chronic glomerolopathy that cause chronic renal disease. Secondary features are: speech disorder delay, developmental delay, polyuria, diabetes mellitus and hypertension. The diagnosis of Bardet- Biedl syndrome is established by clinical findings. Twelve genes are known to be associated with Bardet Biedl syndromes: BBS1, BBS2… BBS12. Case presentation: In this article we report a four and half year old boy that have Bardet Biedl syndrome as a result of a consanguine marriage (third degree. Conclusion: A monogenic syndrome such as Bardet Biedl has a lot of symptoms. These symptoms are out put of a mutation in locus of a recessive allel. Therefore people like to marry consanguinly have to do genetic counseling before marriage. Because analysis of family history will reduced the risk of such syndromes.

  11. Synchrony of oculocutaneous albinism, the Prader-Willi syndrome, and a normal karyotype.

    Science.gov (United States)

    Wallis, C E; Beighton, P H

    1989-01-01

    A Chinese girl with oculocutaneous albinism has the Prader-Willi syndrome and a normal karyotype. This association emphasises the importance of further molecular study of the 15(q12) region of the genome in the search for the locus of an albinism gene. Images PMID:2732995

  12. Usher syndrome type III (USH3) linked to chromosome 3q in an Italian family.

    Science.gov (United States)

    Gasparini, P; De Fazio, A; Croce, A I; Stanziale, P; Zelante, L

    1998-08-01

    We report an Italian family affected by Usher type III syndrome. Linkage study, performed using markers corresponding to the Usher loci already mapped, clearly showed linkage with markers on chromosome 3q24-25. Our data further support the presence of an Usher III locus on chromosome 3, as recently reported in a Finnish population.

  13. Usher syndrome type III (USH3) linked to chromosome 3q in an Italian family.

    OpenAIRE

    Gasparini, P; De Fazio, A; Croce, A I; Stanziale, P; Zelante, L

    1998-01-01

    We report an Italian family affected by Usher type III syndrome. Linkage study, performed using markers corresponding to the Usher loci already mapped, clearly showed linkage with markers on chromosome 3q24-25. Our data further support the presence of an Usher III locus on chromosome 3, as recently reported in a Finnish population.

  14. The role of corneal endothelial morphology in graft assessment and prediction of endothelial cell loss during organ culture of human donor corneas.

    Science.gov (United States)

    Hermel, Martin; Salla, Sabine; Fuest, Matthias; Walter, Peter

    2017-03-01

    Endothelial assessment is crucial in the release of corneas for grafting. We retrospectively analysed the role of endothelial morphology parameters in predicting endothelial cell loss during organ culture. Human donor corneas were cultured in minimal essential medium with 2% fetal calf serum and antibiotics. Initial endothelial morphology was assessed microscopically using score parameters polymegethism (POL), pleomorphism (PLE), granulation (GRA), vacuolization (VAC), segmentation of cell membranes (SEG), Descemet's folds (DF), trypan blue-positive cells (TBPC) and endothelial cell-free areas (ECFA). Some corneas were primarily rejected based on endothelial assessment. Endothelial cell density (ECD) was assessed at the beginning (I-ECD) and end of culture. Corneas were then placed in dehydration medium (as above + 5% dextran 500). In a subgroup, ECD was reassessed after dehydration. Endothelial cell loss during culture (ECL@Culture) and culture+dehydration (ECL-Culture&Dehydration) were calculated. Data were given as mean ± SD and analysed using multiple linear and logistic regression. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. I-ECD was 2812 ± 360/mm 2 (n = 2356). The decision to reject a cornea due to endothelial assessment was associated negatively with I-ECD (OR = 0.77/100 cells, CI 0.7-0.82) and positively with ECFA (OR = 2.7, CI 1.69-4.35), SEG (OR =1.3, CI 1.01-1.68) and donor age (OR = 1.26/decade, CI 1.33-1.41). ECL@Culture was 153 ± 201/mm 2 (n = 1277), ECL@Culture&Dehydration was 169 ± 183/mm 2 (n = 918). ECL@Culture was associated positively with donor age, I-ECD, GRA and TBPC, and negatively with PLE, and DF. ECL@Culture&Dehydration was associated positively with age, sex, initial ECD, POL, PLE, VAC and TBPC. Morphological parameters displayed associations with the exclusion of corneas from culture and with endothelial cell loss. Appropriate parameter selection for screening purposes may help improve

  15. Estudo comparativo entre duas plataformas para realização de Lasik personalizado para correção de miopia e astigmatismo: Alcon CustomCornea® versus Bausch & Lomb Zyoptix® Wavefront-Guided Lasik for low to moderate myopia: CustomCornea® versus Zyoptix®

    Directory of Open Access Journals (Sweden)

    Telma Pereira Barreiro

    2009-08-01

    Full Text Available OBJETIVO: Comparar os resultados obtidos após o Lasik personalizado utilizando duas plataformas diferentes. MÉTODOS: Estudo prospectivo, randomizado com 50 pacientes míopes submetidos a cirurgia refrativa em ambos os olhos. Foram selecionados para o estudo, pacientes com equivalente esférico semelhante entre os olhos. Todos foram submetidos a Lasik bilateral e simultâneo, sendo que um olho foi operado pela plataforma CustomCornea® e o outro pela Zyoptix®. Acuidade visual sem e com correção, refração dinâmica e estática, medida das aberrações oculares, teste de sensibilidade ao contraste foram realizados no período pré-operatório e pós-operatório de 1, 3 e 6 meses. RESULTADOS: No período pré-operatório a média do equivalente esférico era de -3,29 ± 1,56 D no grupo CustomCornea® e de -3,22 ± 1,50 D no Zyoptix® (p=0,267. No sexto mês de pós-operatório, a média do equivalente esférico no grupo CustomCornea® era de -0,077 ± 0,23 D e -0,282 ± 0,30 D no Zyoptix® (p 20/20 foi alcançada em 86% dos olhos no grupo CustomCornea® e 70% no grupo Zyoptix® (p=0,094. Nenhum paciente perdeu duas ou mais linhas da melhor acuidade visual corrigida. Cem por cento dos olhos CustomCornea® e 88% dos Zyoptix® ficaram entre ± 0,50 D da emetropia (p=0,014*. Melhora da sensibilidade ao contraste em todas as frequências espaciais testadas foi observada em ambos os grupos. A aberração esférica apresentou aumento em ambos os grupos, porém este foi estatisticamente maior na plataforma Zyoptix® (pPURPOSE: To compare the visual and clinical outcomes of Wavefront-guided laser in situ keratomileusis (Lasik with Alcon CustomCornea® and Zyoptix® systems. METHODS: A prospective, randomized, masked and bilateral study was conducted. Fifty patients with preoperative spherical equivalent ranging from -1.00 to -6.50 D were enrolled for customized ablation in both eyes. All of them were submitted to Lasik CustomCornea® treatment in one

  16. Urofacial syndrome

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    Kamal F Akl

    2012-01-01

    Full Text Available The urofacial syndrome is characterized by functional obstructive uropathy asso-ciated with an inverted smile. The importance of the subject is that it sheds light, not only on the muscles of facial expression, but also on the inheritance of voiding disorders and lower urinary tract malformations. We report a 10-year-old-male patient who had the urofacial syndrome. Early diagnosis of the urofacial syndrome is important to avoid upper urinary tract damage and renal failure.

  17. Refeeding syndrome

    OpenAIRE

    Tripathy, Swagata; Mishra, Padmini; Dash, S. C.

    2008-01-01

    Refeeding syndrome is a potentially fatal medical condition that may affect malnourished patients in response to an inappropriately rapid overfeeding. This commonly occurs following the institution of nutritional support, especially parenteral or enteral nutrition. The most characteristic pathophysiology of refeeding syndrome relates to the rapid consumption of phosphate after glucose intake and subsequent hypophosphatemia. Refeeding syndrome can manifest as either metabolic changes (hypokala...

  18. Revesz syndrome

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    Dayane Cristine Issaho

    2015-04-01

    Full Text Available Revesz syndrome is a rare variant of dyskeratosis congenita and is characterized by bilateral exudative retinopathy, alterations in the anterior ocular segment, intrauterine growth retardation, fine sparse hair, reticulate skin pigmentation, bone marrow failure, cerebral calcification, cerebellar hypoplasia and psychomotor retardation. Few patients with this syndrome have been reported, and significant clinical variations exist among patients. This report describes the first Brazilian case of Revesz syndrome and its ocular and clinical features.

  19. Different regions of the immunoglobulin heavy-chain locus are involved in chromosomal translocations in distinct pathogenic forms of Burkitt lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Neri, A.; Barriga, F.; Knowles, D.M.; Magrath, I.T.; Dalla-Favera, R.

    1988-04-01

    The authors show that endemic (eBL), sporadic (sBL), and acquired immunodeficiency syndrome-associated (AIDS-BL) forms of Burkitt lymphoma (BL) carrying t(8; 14) chromosomal translocations display different breakpoints within the immunoglobulin heavy-chain locus (IGH) on chromosome 14. In sBL (7 out of 11) and AIDS-BL (5 out of 6), the breakpoints occurred within or near the IGH ..mu.. switch (S/sub mu/) region on chromosome 14 and within the c-myc locus (MYC) on chromosome 8. In most eBL (13 out of 16) the breakpoints were mapped within or 5' to the IGH joining J/sub H/ region on chromosome 14 and outside the MYC locus on chromosome 8. Cloning and sequencing of the (8; 14) chromosomal junctions from two eBL cell lines and one eBL biopsy sample show that the recombination do not involve IGH-specific recombination signals on chromosome 14 or homologous sequences on chromosome 8, suggesting that these events are not likely to be mediated by the same mechanisms or enzymes as in IGH rearrangements. In general, these data have implications for the timing of occurrence of chromosomal translocations during B-cell differentiation in different BL types.

  20. Factor structure, reliability, and validity of the Levenson's Locus of Control Scale in Iranian infertile people.

    Science.gov (United States)

    Maroufizadeh, Saman; Omani Samani, Reza; Amini, Payam; Navid, Behnaz

    2016-09-01

    This study examined psychometric properties of the Levenson's Locus of Control Scale among Iranian infertile patients. In all, 312 infertile patients completed the Levenson's Locus of Control Scale and Hospital Anxiety and Depression Scale. The confirmatory factor analysis indicated that the original three-factor model of Levenson's Locus of Control Scale was adequate ( χ 2 / df = 2.139; goodness-of-fit index = 0.88; root mean square error of approximation = 0.061; and standardized root mean square residual = 0.076). The Cronbach's alpha of the subscales ranged from 0.56 to 0.67. The Levenson's Locus of Control Scale subscales significantly correlated with anxiety and depression, showing an acceptable convergent validity. In conclusion, the Levenson's Locus of Control Scale has adequate reliability and validity and can be used to measure locus of control orientation in Iranian infertile patients.