WorldWideScience

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. 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.

  3. Deleterious Mutations in the Zinc-Finger 469 Gene Cause Brittle Cornea Syndrome

    Science.gov (United States)

    Abu, Almogit; Frydman, Moshe; Marek, Dina; Pras, Eran; Nir, Uri; Reznik-Wolf, Haike; Pras, Elon

    2008-01-01

    Brittle cornea syndrome (BCS) is an autosomal-recessive disorder characterized by a thin cornea that tends to perforate, causing progressive visual loss and blindness. Additional systemic symptoms such as joint hypermotility, hyperlaxity of the skin, and kyphoscoliosis place BCS among the connective-tissue disorders. Previously, we assigned the disease gene to a 4.7 Mb interval on chromosome 16q24. In order to clone the BCS gene, we first narrowed the disease locus to a 2.8 Mb interval and systematically sequenced genes expressed in connective tissue in this chromosomal segment. We have identified two frameshift mutations in the Zinc-Finger 469 gene (ZNF469). In five unrelated patients of Tunisian Jewish ancestry, we found a 1 bp deletion at position 5943 (5943 delA), and in an inbred Palestinian family we detected a single-nucleotide deletion at position 9527 (9527 delG). The function of ZNF469 is unknown. However, a 30% homology to a number of collagens suggests that it could act as a transcription factor involved in the synthesis and/or organization of collagen fibers. PMID:18452888

  4. Mutations in PRDM5 in Brittle Cornea Syndrome Identify a Pathway Regulating Extracellular Matrix Development and Maintenance

    NARCIS (Netherlands)

    Wright, Emma M. M. Burkitt; Spencer, Helen L.; Daly, Sarah B.; Manson, Forbes D. C.; Zeef, Leo A. H.; Urquhart, Jill; Zoppi, Nicoletta; Bonshek, Richard; Tosounidis, Ioannis; Mohan, Meyyammai; Madden, Colm; Dodds, Annabel; Chandler, Kate E.; Banka, Siddharth; Au, Leon; Clayton-Smith, Jill; Khan, Naz; Biesecker, Leslie G.; Wilson, Meredith; Rohrbach, Marianne; Colombi, Marina; Giunta, Cecilia; Black, Graeme C. M.

    2011-01-01

    Extreme corneal fragility and thinning, which have a high risk of catastrophic spontaneous rupture, are the cardinal features of brittle cornea syndrome (BCS), an autosomal-recessive generalized connective tissue disorder. Enucleation is frequently the only management option for this condition,

  5. Mutations in PRDM5 in Brittle Cornea Syndrome Identify a Pathway Regulating Extracellular Matrix Development and Maintenance

    NARCIS (Netherlands)

    Wright, Emma M. M. Burkitt; Spencer, Helen L.; Daly, Sarah B.; Manson, Forbes D. C.; Zeef, Leo A. H.; Urquhart, Jill; Zoppi, Nicoletta; Bonshek, Richard; Tosounidis, Ioannis; Mohan, Meyyammai; Madden, Colm; Dodds, Annabel; Chandler, Kate E.; Banka, Siddharth; Au, Leon; Clayton-Smith, Jill; Khan, Naz; Biesecker, Leslie G.; Wilson, Meredith; Rohrbach, Marianne; Colombi, Marina; Giunta, Cecilia; Black, Graeme C. M.

    2011-01-01

    Extreme corneal fragility and thinning, which have a high risk of catastrophic spontaneous rupture, are the cardinal features of brittle cornea syndrome (BCS), an autosomal-recessive generalized connective tissue disorder. Enucleation is frequently the only management option for this condition, resu

  6. 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......, 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....... Reduced BMD and atypical dental crown morphology have not been reported previously. We confirm that BCS is associated with mutations in ZNF469. The association with red hair in some individuals with BCS is likely to occur by chance....

  7. Cornea Transplant

    Science.gov (United States)

    ... died from an unknown cause. During your cornea transplant On the day of your cornea transplant, you' ... when you see your eye doctor. Procedures to transplant a portion of the cornea With some types ...

  8. Refined localization of the Prieto-syndrome locus

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Cloudy cornea

    Science.gov (United States)

    ... of lid tissue Computer mapping of the cornea (corneal topography) Schirmer's test for eye dryness Special photographs to measure the cells of the cornea Standard eye exam Ultrasound to measure corneal thickness ...

  10. Brittle cornea syndrome ZNF469 mutation carrier phenotype and segregation analysis of rare ZNF469 variants in familial keratoconus.

    Science.gov (United States)

    Davidson, Alice E; Borasio, Edmondo; Liskova, Petra; Khan, Arif O; Hassan, Hala; Cheetham, Michael E; Plagnol, Vincent; Alkuraya, Fowzan S; Tuft, Stephen J; Hardcastle, Alison J

    2015-01-06

    Brittle cornea syndrome 1 (BCS1) is a rare recessive condition characterized by extreme thinning of the cornea and sclera, caused by mutations in ZNF469. Keratoconus is a relatively common disease characterized by progressive thinning and ectasia of the cornea. The etiology of keratoconus is complex and not yet understood, but rare ZNF469 variants have recently been associated with disease. We investigated the phenotype of BCS1 carriers with known pathogenic ZNF469 mutations, and recruited families in which aggregation of keratoconus was observed to establish if rare variants in ZNF469 segregated with disease. Patients and family members were recruited and underwent comprehensive anterior segment examination, including corneal topography. Blood samples were donated and genomic DNA was extracted. The coding sequence and splice sites of ZNF469 were PCR amplified and Sanger sequenced. Four carriers of three BCS1-associated ZNF469 loss-of-function mutations (p.[Glu1392Ter], p.[Gln1930Argfs*6], p.[Gln1930fs*133]) were examined and none had keratoconus. One carrier had partially penetrant features of BCS1, including joint hypermobility. ZNF469 sequencing in 11 keratoconus families identified 9 rare (minor allele frequency [MAF] ≤ 0.025) variants predicted to be potentially damaging. However, in each instance the rare variant(s) identified, including two previously reported as potentially keratoconus-associated, did not segregate with the disease. The presence of heterozygous loss-of-function alleles in the ZNF469 gene did not cause keratoconus in the individuals examined. None of the rare nonsynonymous ZNF469 variants identified in the familial cohort conferred a high risk of keratoconus; therefore, genetic variants contributing to disease pathogenesis in these 11 families remain to be identified. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  11. 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

    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...

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

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    Farrer, L.A.; Hoth, C. [Boston Univ. School of Medicine, MA (United States); Arnos, K.S. [Galludet Univ., Washington, DC (United States); Asher, J.H. Jr.; Friedman, T.B. [Michigan State Univ., East Lansing, MI (United States); Grundfast, K.M.; Lalwani, A.K. [National Institute on Deafness and Other Communication Disorders, Bethesda, MD (United States); Greenberg, J. [Univ. of Cape Town (South Africa); Diehl, S.R. [and others

    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. 59 refs., 3 figs., 5 tabs.

  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. Scheie syndrome

    Science.gov (United States)

    ... Hurler syndrome) MPS II (Hunter syndrome) MPS IV (Morquio syndrome) MPS III (Sanfilippo syndrome) Causes Scheie syndrome ... Autosomal recessive Cloudy cornea Hearing loss Hurler syndrome Morquio syndrome Review Date 4/20/2015 Updated by: ...

  15. 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

    family of Iraqi descent. By homozygosity mapping a new locus for the syndrome was assigned to a approximately 30 cM interval between markers D18S78 and D18S866 with a maximum multipoint lod score of 3.1, corresponding to a trans-centromeric region on chromosome 18p11.31-q11.2. This second locus...

  16. Major-locus contributions to variability of the craniofacial feature dystopia canthorum in Waardenburg syndrome

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    Reynolds, J.E.; Meyer, J.M.; Stevens, C.A. [Virginia Commonwealth Univ., Richmond, VA (United States)] [and others

    1996-02-01

    We used segregation analysis to investigate the genetic basis of variation in dystopia canthorum, one of the key diagnostic features of Waardenburg syndrome type 1 (WS1). We sought to determine whether the W-index, a quantitative measure of this craniofacial feature, is influenced primarily either by allelic variation in the PAX3 disease gene or other major loci, by polygenic background effects, or by all of these potential sources of genetic variation. We studied both WS1-affected individuals and their WS1-unaffected relatives. After adjustment of the W-index for WS1 disease status, segregation analyses by the regression approach indicated major-locus control of this variation, although residual parent-offspring and sib-sib correlations are consistent with additional (possibly polygenic) effects. Separate analyses of WS1-affected and WS1-unaffected individuals suggest that epistatic interactions between disease alleles at the PAX3 WS1 locus and a second major locus influence variation in dystopia canthorum. Our approach should be applicable for assessing the genetic architecture of variation associated with other genetic diseases. 23 refs., 1 fig., 6 tabs.

  17. Major-locus contributions to variability of the craniofacial feature dystopia canthorum in Waardenburg syndrome.

    Science.gov (United States)

    Reynolds, J E; Marazita, M L; Meyer, J M; Stevens, C A; Eaves, L J; Arnos, K S; Ploughman, L M; MacLean, C; Nance, W E; Diehl, S R

    1996-02-01

    We used segregation analysis to investigate the genetic basis of variation in dystopia canthorum, one of the key diagnostic features of Waardenburg syndrome type 1 (WS1). We sought to determine whether the W-index, a quantitative measure of this craniofacial feature, is influenced primarily either by allelic variation in the PAX3 disease gene or other major loci, by polygenic background effects, or by all of these potential sources of genetic variation. We studied both WS1-affected individuals and their WS1-unaffected relatives. After adjustment of the W-index for WS1 disease status, segregation analyses by the regression approach indicated major-locus control of this variation, although residual parent-offspring and sib-sib correlations are consistent with additional (possibly polygenic) effects. Separate analyses of WS1-affected and WS1-unaffected individuals suggest that epistatic interactions between disease alleles at the PAX3 WS1 locus and a second major locus influence variation in dystopia canthorum. Our approach should be applicable for assessing the genetic architecture of variation associated with other genetic diseases.

  18. A novel locus for Meckel-Gruber syndrome, MKS3, maps to chromosome 8q24.

    Science.gov (United States)

    Morgan, Neil V; Gissen, Paul; Sharif, Saghira Malik; Baumber, Laura; Sutherland, Joan; Kelly, Deirdre A; Aminu, Kingi; Bennett, Christopher P; Woods, C Geoffrey; Mueller, Robert F; Trembath, Richard C; Maher, Eamonn R; Johnson, Colin A

    2002-10-01

    Meckel-Gruber syndrome (MKS), the most common monogenic cause of neural tube defects, is an autosomal recessive disorder characterised by a combination of renal cysts and variably associated features, including developmental anomalies of the central nervous system (typically encephalcoele), hepatic ductal dysplasia and cysts, and polydactyly. Locus heterogeneity has been demonstrated by the mapping of the MKS1locus to 17q21-24 in Finnish kindreds, and of MKS2 to 11q13 in North African-Middle Eastern cohorts. In the present study, we have investigated the genetic basis of MKS in eight consanguineous kindreds, originating from the Indian sub-continent, that do not show linkage to either MKS1 or MKS2. We report the localisation of a third MKS locus ( MKS3) to chromosome 8q24 in this cohort by a genome-wide linkage search using autozygosity mapping. We identified a 26-cM region of autozygosity between D8S586 and D8S1108 with a maximum cumulative two-point LOD score at D8S1179 ( Z(max)=3.04 at theta=0.06). A heterogeneity test provided evidence of one unlinked family. Exclusion of this family from multipoint analysis maximised the cumulative multipoint LOD score at locus D8S1128 ( Z(max)=5.65). Furthermore, a heterozygous SNP in DDEF1, a putative candidate gene, suggested that MKS3 mapped within a 15-cM interval. Comparison of the clinical features of MKS3-linked cases with reports of MKS1- and MKS2-linked kindreds suggests that polydactyly (and possibly encephalocele) appear less common in MKS3-linked families.

  19. Candidate regions for Waardenburg syndrome type II: Search for a second WS locus

    Energy Technology Data Exchange (ETDEWEB)

    Nance, W.E.; Pandya, A.; Blanton, S.H. [VA Commonwealth Univ, Richmond, VA (United States)] [and others

    1994-09-01

    Waardenburg syndrome is an autosomal dominant disorder characterized by deafness and pigmentary abnormalities such as heterochromia of irides, hypopigmented skin patches, white forlock and premature graying. Clinically the syndrome has been classified into three types. Type II differs from type I in that dystopia canthorum is generally absent, and type III has associated limb anomalies. Recently linkage analysis localized the gene for WSI to chromosome 2q. PAX-3, which is a human analogue of the murine pax-3 locus, maps to this region and mutations in this gene have been found to segregate with WSI. However genetic heterogeneity clearly exists: most if not all WSII families are unlinked to PAX-3 while most if not all WSI cases are linked. We ascertained a four-year-old female child with an interstitial deletion of chromosome 13 who had features of WS including bilateral congenital sensorineural hearing loss, pale blue irides and pinched nostrils as well as hypertelorism microcephaly, bilateral eyelid ptosis, digitalization of thumbs and fifth finger clinodactyly. High resolution chromosomal analysis revealed a de novo interstitial deletion of 13q22-33.2. There was no family history of WS or retardation. A similar deletion in the region of 13q21-32 has been described in a 13-year-old boy with features of WSII. These two cases strongly suggested that this chromosomal region may include a second locus for WS. We have identified eight families with clinical features of WS type I which have been excluded from linkage to the PAX-3 locus. We have typed these families for microsatellite markers spanning chromosome 13. Linkage between WSII and the chromosome 13 markers was excluded in these families. Hirschsprung disease has been associated with WS and it has recently been mapped to chromosome 10q11.2-q21.1. We are currently typing the 8 families for microsatellites in this region.

  20. Atypical Aicardi-Goutieres syndrome: is the WRN locus a modifier?

    Science.gov (United States)

    Lessel, Davor; Saha, Bidisha; Hisama, Fuki; Kaymakamzade, Bahar; Nurlu, Gulay; Gursoy-Özdemir, Yasemin; Thiele, Holger; Nürnberg, Peter; Martin, George M; Kubisch, Christian; Oshima, Junko

    2014-10-01

    We describe a 28-year-old Turkish man with consanguineous parents who presented with an aged appearance with prematurely gray hair and scleroderma-like skin, spastic paraplegia, and apparent disability. The proband and each of his parents were heterozygous for a mutation in WRN, which could not explain his symptoms. Exome sequencing of the proband's blood DNA showed a homozygous c.626-1G > C mutation in intron 5 of the SAMHD1 gene, which encodes a triphosphohydrolase involved in the regulation of intracellular dNTP pools and which is mutated in Aicardi-Goutieres syndrome. The RNA studies confirmed aberrant splicing of exon 6, and family studies showed that both parents are heterozygous for this mutation. We conclude that mutations in SAMHD1 - in addition to causing an early-onset form of encephalopathy in Aicardi-Goutieres syndrome - may present with modest signs of accelerated aging similar to Werner syndrome. The extent to which heterozygosity at the WRN locus may modify the effect of biallelic SAMHD1 mutations is unknown. It is conceivable that synergistic effects of these two mutations might be responsible for the unusual phenotype.

  1. Transcription mapping of the region containing the locus for Treacher Collins syndrome

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    Wise, C.A.; Gallardo, T.D. [Univ. of Texas Southwestern Medical Center, Dallas, TX (United States); Li, X. [Johns Hopkins Univ., Baltimore, MD (United States)] [and others

    1994-09-01

    Treacher Collins syndrome, an autosomal dominant craniofacial disorder and the most common mandibulofacial dysostosis disorder, has been genetically localized to chromosome 5q32. We have previously constructed a YAC contig of approximately 3 megabases cross the region that includes this locus. A single 1.6 Mb YAC from within this contig contains the genetic markers that flank the disease locus as well as two known genes, osteonectin (SPARC) and annexin VI (ANX6). This was converted to cosmid clones by using inter-Alu PCR products from the YAC to screen the LANL chromosome 5-specific cosmid library. One hundred and seventy five cosmids covering the candidate interval were used in a direct selection strategy to enrich for cDNAs encoded by this region. Over 30 selected cDNAs derived from fetal face, fetal brain, activated T cells, placenta, and fetal cranial tissues have been mapped to the region and DNA sequenced. The majority of these cDNAs show little or no homology to previously described DNA sequences. However, one known gene encoding the G (M2) activator protein was selected as a cDNA and mapped to the region immediately flanking the ANX6 locus. A partial cosmid contig covering the critical interval was built from the cosmids by a combination of end walking and fingerprinting methods. Additional polymorphic markers developed from the contig have allowed the Treacher Collins critical region to be further refined to less than 500 kb. Full length cDNA clones that map to this smaller critical region are currently being derived and evaluated in affected pedigrees.

  2. A TCTN2 mutation defines a novel Meckel Gruber syndrome locus.

    Science.gov (United States)

    Shaheen, Ranad; Faqeih, Eissa; Seidahmed, Mohammed Z; Sunker, Asma; Alali, Faten Ezzat; AlQahtani, Khadijah; Alkuraya, Fowzan S

    2011-06-01

    Meckel Gruber syndrome (MKS) is an autosomal recessive multisystem disorder that represents a severe form of ciliopathy in humans and is characterized by significant genetic heterogeneity. In this article, we describe the identification of a novel MKS locus MKS8 that we map to TCTN2, in a multiplex consanguineous family. TCTN2 is a paralog of the recently identified Tectonic 1, which has been shown to modulate sonic hedgehog signaling. Expression analysis at different developmental stages of the murine ortholog revealed a spatial and temporal pattern consistent with the MKS phenotype observed in our patient. The exclusion of this and the other seven MKS genes in our collection of consanguineous Arab MKS families confirms the existence of two additional MKS loci. © 2011 Wiley-Liss, Inc.

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

    Science.gov (United States)

    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.

  4. The locus for a novel syndromic form of neuronal intestinal pseudoobstruction maps to Xq28.

    Science.gov (United States)

    Auricchio, A; Brancolini, V; Casari, G; Milla, P J; Smith, V V; Devoto, M; Ballabio, A

    1996-04-01

    The neuronal type of primary chronic idiopathic intestinal pseudoobstruction (CIIP) results from the developmental failure of enteric neurons to migrate or differentiate correctly. This leads to intestinal motility disorders, which are characterized by symptoms and signs of bowel obstruction in the absence of a mechanical obstacle. Most of these conditions are congenital, and among them some are inherited. One syndromic condition characterized by intestinal pseudoobstruction with morphological abnormalities of the argyrophil neurons in the myenteric plexus, associated with short small bowel, malrotation, and pyloric hypertrophy, has been previously described. We have studied a family affected by this disorder, in which the disease appeared to segregate as an X-linked recessive trait. In order to map the CIIP locus in this family, we performed linkage analysis in 26 family members by use of highly polymorphic microsatellite markers from the X chromosome. One of these markers, DXYS154, located in the distal part of Xq28, shows no recombination with a maximum lod score of 2.32. Multipoint analysis excluded linkage with markers spanning other regions of the X chromosome. Our results, integrated with the current genetic and physical map of Xq28, determine the order of loci as cen-DXS15-(CIIPX)-DXS1108/DXYS154-tel. This study establishes, for the first time, the mapping assignment of a neuropathic form of CIIP other than Hirschsprung disease.

  5. The locus for a novel syndromic form of neuronal intestinal pseudoobstruction maps of Xq28

    Energy Technology Data Exchange (ETDEWEB)

    Auricchio, A.; Casari, G.; Ballabio, A. [Telethon Inst. of Genetics and Medicine, Milan (Italy); Brancolini, V.; Devoto, M. [Columbia Univ., New York, NY (United States)] [and others

    1996-04-01

    The neuronal type of primary chronic idiopathic intestinal pseudoobstruction (CIIP) results from the developmental failure of enteric neurons to migrate or differentiate correctly. This leads to intestinal motility disorders, which are characterized by symptoms and signs of bowel obstruction in the absence of a mechanical obstacle. Most of these conditions are congenital, and among them some are inherited. One syndromic condition characterized by intestinal pseudoobstruction with morphological abnormalities of the argyrophil neurons in the myenteric plexus, associated with short small bowel, malrotation, and pyloric hypertrophy, has been previously described. We have studied a family affected by this disorder, in which the disease appeared to segregate as an X-linked recessive trait. In order to map the CIIP locus in this family, we performed linkage analysis in 26 family members by use of highly polymorphic microsatellite markers from the X chromosome. One of these markers, DXYS154, located in the distal part of Xq28, shows no recombination with a maximum lod score of 2.32. Multipoint analysis excluded linkage with markers spanning other regions of the X chromosome. Our results, integrated with the current genetic and physical map of Xq28, determine the order of loci as cen-DXS15-(CIIPX)-DXS1108/DXYS154-tel. This study establishes, for the first time, the mapping assignment of a neuropathic form of CIIP other than Hirschsprung disease. 31 refs., 3 figs., 1 tab.

  6. The osteoporosis-pseudoglioma syndrome locus is on chromosome 11q

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Y.; Vikkula, M.; Boon, L.M. [Harvard Medical School, Boston, MA (United States)] [and others

    1994-09-01

    The osteoporosis-pseudoglioma syndrome (OPS), is a rare autosomal recessive disorder characterized by severe osteoporosis with multiple fractures and blindness, both occurring in childhood. The precise pathogenic mechanism for OPS is unknown. Insights into its cause may be useful towards understanding the pathophysiology of more common disorders, such as senile osteoporosis, persistent hyperplasia of the primary vitreous, and retinopathy of prematurity, whose features have some similarity with OPS. As a first step in determining the cause of OPS, we have mapped the locus of the disorder to chromosome 11q. This was accomplished by assuming genetic homogeneity and by performing linkage analysis with homozygosity mapping in 18 individuals (7 patients, 5 unaffected siblings, and 7 parents) from 3 different consanguineous kindreds. Since the condition could be caused by an abnormal extracellular matrix component, we began by testing several candidate genes (e.g., COL1A1, COL1A2, Osteopontin, Osteonectin) distributed on 12 different chromosomes. We also initiated a systematic search at 20 cM intervals with highly polymorphic simple sequence tandem repeats. Linkage and homozygosity was detected with marker D11S913 (LOD score 3.8 at {theta} = 0). Additional markers are being tested to confirm this observation. The fibroblast collagenase, fibronectin-like-2 gene and rod outer segment protein-1 (ROM 1) also map to chromosome 11q and are candidate genes.

  7. Gene locus ambiguity in posterior urethral valves/prune-belly syndrome.

    Science.gov (United States)

    Weber, Stefanie; Mir, Sevgi; Schlingmann, Karl Peter; Nürnberg, Gudrun; Becker, Christian; Kara, Pelin E; Ozkayin, Nese; Konrad, Martin; Nürnberg, Peter; Schaefer, Franz

    2005-08-01

    Lower urinary tract obstruction by posterior urethral valves (PUV) is an important cause of congenital renal failure in male infants. Though population-based studies point to a role of genetic factors in the etiology of PUV, no clear evidence for a specific gene defect for PUV has been observed so far. Here we present a consanguineous family with four male descendants affected by PUV and a healthy girl, suggestive of autosomal recessive inheritance. One boy presented with prune-belly syndrome (PBS) in addition to PUV. Using a DNA chip-based genome-wide linkage analysis, we identified a region of homozygosity for the affected boys in an interval of 35 cM on chromosome 1q41-44 with a maximum multipoint LOD score of Z(max) = 3.134 at theta = 0 for single nucleotide polymorphisms (SNPs) rs158724-rs720163. By applying a second genetic model based on the assumption of a male-limited phenotype and the girl being carrier of the genetic defect without expressing the phenotype, a second alternative locus of 9 cM on chromosome 11p11 was identified with a LOD score of Z(max) = 3.61 at theta = 0. Equal significance for both loci with a LOD score of Z(max) = 3.01 at theta = 0 was obtained after the affection status of the female descendant was set "unknown". We suppose that most probably, only one of the two identified loci harbours the disease-causing gene. As the interpretation of the girl's status remains uncertain, we are not able to exclude one of the two loci. Analyses of additional informative families will be important to exclude one of the two loci and to restrict the critical interval.

  8. 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

    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...

  9. The cornea in measles

    NARCIS (Netherlands)

    N.W.H.M. Dekkers (Nico)

    1981-01-01

    textabstractThe involvement of the cornea in the acute stage of measles is the subject of the present study. The best study on the measles-keratitis now available is still the one by Trantas in 1903. It seems wo.:thwhile therefore to study this self-limiting keratitis with the investigative tools

  10. The cornea in measles

    NARCIS (Netherlands)

    N.W.H.M. Dekkers (Nico)

    1981-01-01

    textabstractThe involvement of the cornea in the acute stage of measles is the subject of the present study. The best study on the measles-keratitis now available is still the one by Trantas in 1903. It seems wo.:thwhile therefore to study this self-limiting keratitis with the investigative tools no

  11. A case of Feingold type 2 syndrome associated with keratoconus refines keratoconus type 7 locus on chromosome 13q.

    Science.gov (United States)

    Sirchia, Fabio; Di Gregorio, Eleonora; Restagno, Gabriella; Grosso, Enrico; Pappi, Patrizia; Talarico, Flavia; Savin, Elisa; Cavalieri, Simona; Giorgio, Elisa; Mancini, Cecilia; Pasini, Barbara; Mehta, Jodhbir S; Brusco, Alfredo

    2017-04-01

    We report on a 58-year old woman with microcephaly, mild dysmorphic features, bilateral keratoconus, digital abnormalities, short stature and mild cognitive delay. Except for keratoconus, the phenotype was suggestive for Feingold syndrome type 2 (FGLDS2, MIM 614326), a rare autosomal dominant disorder described in six patients worldwide, due to the haploinsufficiency of MIR17HG, a micro RNA encoding gene. Karyotype showed a de novo deletion on chromosome 13q, further defined by array-Comparative Genomic Hybridization (a-CGH) to a 17.2-Mb region. The deletion included MIR17HG, as expected by the FGLDS2 phenotype, and twelve genes from the keratoconus type 7 locus. Because our patient presented with keratoconus, we propose she further refines disease genes at this locus. Among previously suggested candidates, we exclude DOCK9 and STK24, and propose as best candidates IPO5, DNAJC3, MBNL2 and RAP2A. In conclusion, we report a novel phenotypic association of Feingold syndrome type 2 and keratoconus, a likely contiguous gene syndrome due to a large genomic deletion on 13q spanning MIR17HG and a still to be identified gene for keratoconus. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. A novel locus for syndromic chronic idiopathic intestinal pseudo-obstruction maps to chromosome 8q23-q24.

    Science.gov (United States)

    Deglincerti, Alessia; De Giorgio, Roberto; Cefle, Kivanc; Devoto, Marcella; Pippucci, Tommaso; Castegnaro, Giovanni; Panza, Emanuele; Barbara, Giovanni; Cogliandro, Rosanna F; Mungan, Zeynel; Palanduz, Sukru; Corinaldesi, Roberto; Romeo, Giovanni; Seri, Marco; Stanghellini, Vincenzo

    2007-08-01

    Chronic idiopathic intestinal pseudo-obstruction (CIIP) is a rare and severe clinical syndrome characterized by symptoms and signs of intestinal occlusion, in the absence of any mechanical obstruction of the gut lumen. In the attempt to identify the genetic basis of CIIP, we analyzed a Turkish pedigree with a high degree of consanguinity in which three siblings presented with a syndromic form of CIIP. All affected family members were characterized by recurrent, self-limiting subocclusive episodes, long-segment Barrett esophagus, and a variety of minor cardiac valve or septal defects. In some patients full-thickness intestinal biopsy samples were obtained and tissues were processed for immunohistochemistry using antibodies to different markers of the intestinal neuromuscular tract. Full-thickness biopsies of the gut wall showed abnormalities of both the neural and muscular components suggesting an underlying intestinal neuro-myopathy. Blood samples were collected for DNA extraction from each available family member and DNAs were genotyped using 382 microsatellites spanning the entire genome with the aim to take advantage of the homozygosity mapping approach. Linkage analysis identified a new syndromic locus on chromosome 8q23-q24 (multipoint LOD score=5.01). Our data strongly support the presence of a new genetic locus associated with CIIP, long-segment Barrett esophagus, and cardiac involvement on chromosome 8.

  13. Genomewide association study reveals a risk locus for equine metabolic syndrome in the Arabian horse.

    Science.gov (United States)

    Lewis, S L; Holl, H M; Streeter, C; Posbergh, C; Schanbacher, B J; Place, N J; Mallicote, M F; Long, M T; Brooks, S A

    2017-03-01

    Equine obesity can cause life-threatening secondary chronic conditions, similar to those in humans and other animal species. Equine metabolic syndrome (EMS), primarily characterized by hyperinsulinemia, is often present in obese horses and ponies. Due to clinical similarities to conditions such as pituitary pars intermedia dysfunction (formerly equine Cushing's disease), conclusive diagnosis of EMS often proves challenging. Aside from changes in diet and exercise, few targeted treatments are available for EMS, emphasizing the need for early identification of at-risk individuals to enable implementation of preventative measures. A genomewide association study (GWAS) using Arabian horses with a history of severe laminitis secondary to EMS revealed significant genetic markers near a single candidate gene () that may play a role in cholesterol homeostasis. The best marker, BIEC2-263524 (chr14:69276814 T > C), was correlated with elevated insulin values and increased frequency of laminitis ( = 0.0024 and = 9.663 × 10, respectively). In a second population of Arabian horses, the BIEC2-263524 marker maintained its associations with higher modified insulin-to-glucose ratio (MIRG) values ( = 0.0056) and BCS ( = 0.0063). Screening of the predicted coding regions by sequencing identified a polymorphic guanine homopolymer and 5 haplotypes in the 3' untranslated region (UTR). An 11 guanine (11-G) allele at was correlated with elevated insulin values in the GWAS population ( = 0.0008) and, in the second population, elevated MIRG and increased BCS > 6.5 ( = 0.0055 and = 0.0162, respectively). The BIEC2-263524-C and the 3' UTR -11(G) polymorphisms were correlated at a 98% frequency, indicating strong linkage disequilibrium across this 150-kb haplotype. Assays for these markers could diagnose horses with a genetic predisposition to develop obesity. Additionally, discovery of FAM174A function may improve our understanding of the etiology of this troubling illness in the horse and

  14. Deletion of locus D15S113 in a mother and son without features of Angelman syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Michaelis, R.C.; Tarleton, J.C.; Donlon, T.A.; Simensen, R.J. [Greenwood Gneetic Center, SC (United States)] [and others

    1994-09-01

    Deletions of the proximal long arm of chromosome 15 result in Angelman syndrome when inherited from the mother and Prader-Willi syndrome when inherited from the father. The minimal critical deletion region for Angelman syndrome has been reported to include D15S74 (B1.5), D15S10 (TD3-21), and D15S113 (LS6-1). We report a mother and son who have deletions that include D15S113 but who do not have features of Angelman syndrome. D.H. is a 10-year-old white male referred for genetic evaluation due to mental retardation. He has mild to moderate mental retardation and minor dysmorphic features, including downslanting palpebral fissures, prominent nose, broad forehead, small chin, midface hypoplasia, and large ears. His mother (B.S.) has slightly downslanting palpebral fissures and a borderline intellectual deficit. Neither individual has the seizures, excessive laughter, hand clapping, ataxia or facial dysmorphism which are characteristic of Angelman syndrome. The linear order of probes mapping to 15q11-q13 is 15cen-D15S11-D15S13-D15S10-D15S113-GABRB3-D15S12-tel. The proximal border of the deletion in our patients lies between D15S10 and D15S113. The fact that these two individuals do not have Angelman syndrome, despite deletion of D15S113, suggests that the Angelman syndrome critical deletion region should be further refined to exclude the D15S113 locus. In addition, the findings of a more severe intellectual impairment in the son than in the mother suggests that the region immediately telomeric to the critical deletion region for Angelman syndrome may contain imprintable genes that influence intellectual function.

  15. Genetic heterogeneity among craniosynostosis syndromes: Mapping the Saethre-Chotzen syndrome locus between D7S513 and D7S516 and exclusion of Jackson-Weiss and Crouzon syndrome loci from 7p

    Energy Technology Data Exchange (ETDEWEB)

    Lewanda, A.F.; Taylor, E.W.; Li, Xiang; Beloff, M. (Johns Hopkins School of Medicine, Baltimore, MD (United States)); Cohen, M.M. Jr. (Dalhousie Univ., Nova Scotia (Canada)); Jackson, C.E. (Henry Ford Hospital, Detroit, MI (United States)); Day, D. (Texas Dept. of Health, Denton, TX (United States)); Clarren, S.K. (Univ. of Washington School of Medicine, Seattle, WA (United States)); Ortiz, R.; Garcia, C. (Hospital Infantil de Mexico, Distrito Federal (Mexico)) (and others)

    1994-01-01

    Saethre-Chotzen, Crouzon, and Jackson-Weiss syndromes are craniosynostotic autosomal dominant conditions with a wide variability in expression. Saethre-Chotzen has been mapped to chromosome 7p by L. A. Brueton et al., the Greig cephalopolysyndactyly gene was identified at 7p13 by A. Vortkamp et al., and many cases of craniosynostosis have been associated with 7p deletions. The authors confirmed linkage of the Saethre-Chotzen syndrome locus to chromosome 7p. The tightest linkage was to locus D7S493 (7 = 5.04, [theta] = 0.00), and linkage and haplotype analyses refined the location of the gene to the region between D7S513 and D7S516. Jackson-Weiss and Crouzon syndrome loci were analyzed using markers spanning the entire 7p arm and were excluded, proving that they are nonallelic to Saethre-Chotzen, Greig cephalopolysyndactyly, and the del(7p) syndromes. 29 refs., 1 fig., 2 tabs.

  16. Evidence for locus heterogeneity in acrocephalosyndactyly: a refined localization for the Saethre-Chotzen syndrome locus on distal chromosome 7p--and exclusion of Jackson-Weiss syndrome from craniosynostosis loci on 7p and 5q.

    Science.gov (United States)

    van Herwerden, L; Rose, C S; Reardon, W; Brueton, L A; Weissenbach, J; Malcolm, S; Winter, R M

    1994-04-01

    Craniosynostosis (premature fusion of the skull sutures) occurs as a clinically heterogeneous group of disorders, frequently involving digital abnormalities. We have previously provisionally assigned the gene for one such condition, Saethre-Chotzen syndrome (ACS III), to chromosome 7p. Linkage analysis is now reported between ACS III and dinucleotide repeat loci on distal 7p. The maximum lod scores, Zmax, were 5.57 at a recombination fraction of .05, with D7S488, and 4.74 at a recombination fraction of .05, with D7S493. Only weak linkage, not reaching significance, was found with distal markers (D7S513 and afm281vc9) and a proximal marker (D7S516). Multipoint analysis shows that the disease locus lies between D7S513 and D7S516. Analysis of individual recombinants shows that the most likely position is between D7S493 and D7S516. Linkage data in regard of Jackson-Weiss syndrome demonstrate that this autosomal dominant form of acrocephalosyndactyly does not map to the ACS III region on 7p or to the acrocephalosyndactyly locus on 5q (Boston type). These findings underline the genetic heterogeneity among the different clinical conditions manifesting with acrocephalosyndactyly.

  17. Evidence for locus heterogeneity in acrocephalosyndactyly: A refined localization for the Saethre-Chotzen syndrome locus on distal chromosome 7p-and exclusion of Jackson-Weiss syndrome from craniosynostosis loci on 7p and 5q

    Energy Technology Data Exchange (ETDEWEB)

    Herwerden, L. van; Rose, C.S.P.; Reardon, W.; Malcolm, S.; Winter, R.M. (Institute of Child Health, London (United Kingdom)); Brueton, L.A. (Northwick Park Hospital, Harrow (United Kingdom)); Weissenbach, J. (Human Genome Research Centre, Evry (France))

    1994-04-01

    Craniosynostosis (premature fusion of the skull sutures) occurs as a clinically heterogeneous group of disorders, frequently involving digital abnormalities. The authors have previously provisionally assigned the gene for one such condition, Saethre-Chotzen syndrome (ACS III), to chromosome 7p. Linkage analysis is now reported between ACS III and dinucleotide repeat loci on distal 7p. The maximum lod scores, Z[sub max], were 5.57 at a recombination fraction of .05, with D7S488, and 4.74 at a recombination fraction of .05, with D7S493. Only weak linkage, not reaching significance, was found with distal markers (D7S513 and afm281vc9) and a proximal marker (D7S516). Multipoint analysis shows that the disease locus lies between D7S513 and D7S516. Analysis of individual recombinants shows that the most likely position is between D7S493 and D7S516. Linkage data in regard of Jackson-Weiss syndrome demonstrate that this autosomal dominant form of acrocephalosyndactyly does not map to the ACS III region on 7p or to the acrocephalosyndactyly locus on 5q (Boston type). These findings underline the genetic heterogeneity among the different clinical conditions manifesting with acrocephalosyndactyly. 20 refs., 3 figs., 2 tabs.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  20. Haplotype analysis of DNA microsatellites tightly linked to the locus of Usher syndrome type I on chromosome 11q

    Energy Technology Data Exchange (ETDEWEB)

    Korostishevsky, M.; Kalinsky, H.; Seroussi, E. [Sackler Faculty of Medicine, Ramat-Aviv (Israel)] [and other

    1994-09-01

    Usher syndrome type I (USHI), an autosomal recessive disorder associated with congenital sensorineural deafness and progressive visual loss, is closely linked to the D11S533 locus. The availability of 7 other polymorphic markers within few centimorgans spanning the disease locus allowed us to identify a unique and single haplotype among all carriers of USHI gene in the Samaritan kindred. Occurrence of recombination in this small chromosomal interval is rare, hindering the detection of the mitotic recombination events needed for analysis by traditional linkage methods. Attempts to order the eight loci by linkage disequilibrium models proved to be problematic. However, our haplotype analysis implied that recombinations which had arisen in past generations may be utilized in fine mapping of the USHI gene and in resolving the conflicting linkage maps previously obtained for this region. We have developed a simple algorithm for predicting the order of the microsatellites on the basis of haplotype resemblance. The following chromosomal map in which the USHI gene is closest to D11S533 (location score of 31.0 by multipoint analysis) is suggested: D11S916, GARP, D11S527, D11S533, OMP, D11S906, D11S911, D11S937. Physical mapping efforts are currently directed to verify and to detail the map of this chromosomal region.

  1. A novel microsatellite DNA marker at locus D7S1870 detects hemizygosity in 75% of patients with Williams syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert-Dussardier, B. [Hopital des Enfants-Malades, Paris (France)]|[Hopital Dupuytren, Limoges (France); Bonneau, D. [Hopital des Enfants-Malades, Paris (France)]|[Hopital Jean Bernard, Poitiers (France); Gigarel, N.; Le Merrer, M.; Bonnet, D.; Lyonnet, S.; Munnich, A. [Hopital des Enfants-Malades, Paris (France); Philip, N.; Mattei, M.G. [Hopital de La Timone, Marseille (France)] [and others

    1995-02-01

    Williams syndrome (WS) is a predominantly sporadic developmental disorder characterized by dysmorphic facial features, infantile hypercalcemia, premature aging of skin, mental retardation and gregarious personality. Supravalvular aortic stenosis (SVAS) and other vascular diseases caused by the narrowing of large elastic arteries are present in almost 80% of cases. Recently, hemizygosity at the elastin locus has been shown in sporadic WS, suggesting that this disease is caused by deletions encompassing the elastin gene on chromosome 7q11.23. Taking advantage of a large series of sporadic WS (27 cases), we have explored the potential application of novel microsatellite DNA markers in the rapid detection of hemizygosity in WS. We report here a highly informative marker at locus D7S1870, which detected failure of parental inheritance in almost 75% of cases of WS in our series. This marker can be regarded therefore as a reliable and useful diagnostic tool in suspected cases of WS as well as in complicated forms of supravalvular aortic stenosis. 10 refs., 2 figs.

  2. Phototoxicity and the cornea.

    Science.gov (United States)

    Schein, O D

    1992-07-01

    The cornea is sensitive to the effects of ultraviolet (UV) light and can suffer both acute and chronic toxicity. Ultraviolet keratitis is associated with relatively short exposures to light sources such as welding arcs or tanning lamps. The corneal effects are seen within a few hours following exposure and typically will resolve within 72 hours. Chronic exposure to environmental UV light may lead to a variety of ocular surface abnormalities that rarely resolve in the absence of therapy. Ultraviolet light, while potentially destructive, also can be used therapeutically. Recently, the photoablative properties of the excimer laser have been used in corneal refractive surgery. This laser uses UV light to break chemical bonds and remove tissue. Corneal phototoxicity is a reflection of the sensitivity of the ocular surface to photochemical injury. Fortunately, effective protection in the form of UV-blocking lenses is widely available.

  3. Evidence that methylation of the FMR-I locus is responsible for variable phenotypic expression of the fragile X syndrome

    Energy Technology Data Exchange (ETDEWEB)

    McConkie-Rosell, A.; Lachiewicz, A.M.; Spiridigliozzi, G.A.; Shoenwald, S. (Duke Univ., Durham, NC (United States)); Tarleton, J.; Phelan, M.C. (Greenwood Genetics Center, Greenwood, SC (United States)); Goonewardena, P. (Kaiser Permanente, San Jose, CA (United States)); Ding, X.; Brown, W.T. (Institute for Basic Research in Developmental Disabilities, Staten Island, NY (United States))

    1993-10-01

    DNA at the FMR-1 locus was analyzed by Southern blot using probe StB12.3 in an unusual fragile X family with six brothers, three of whom are affected with fragile X to varying degrees, two of whom are nonpenetrant carriers, and one of whom is unaffected. Fragile X chromosome studies, detailed physical examinations, and psychological testing were completed on all six. Two of the affected brothers and the two nonpenetrant brothers were found to be methylation mosaics. The three affected males spanned the phenotypic and cognitive spectrum of the fragile X syndrome. A correlation was seen between the degree of methylation and the phenotypic expression identified in the three affected males. The two males initially classified as nonpenetrant were found to have mild phenotypic expression which consisted of minor cognitive deficits and a partial physical phenotype. These two, who were negative on fragile X chromosome studies, were found on DNA analysis to have large broad smears, with approximately 97% of the DNA unmethylated. The results described here indicate that some [open quotes]nonpenetrant[close quotes] carrier males may have varying amounts of methylation of the FMR-1 region, which can result in mild expression of the fragile X syndrome. The apparently mild phenotypic and cognitive expression of the fragile X syndrome in the two males, initially classified as nonpenetrant, who are mosaic for hypermethylation of an expansion of the CGG repeat in the premutation range, indicates that expression of the syndrome is not confined to males with large, hypermethylated expansions (full mutation) but has instead a gradient effect with a threshold for the full expression of the phenotype. 41 refs., 2 tabs.

  4. A novel locus for alopecia with mental retardation syndrome (APMR2) maps to chromosome 3q26.2-q26.31.

    Science.gov (United States)

    Wali, A; John, P; Gul, A; Lee, K; Chishti, M S; Ali, G; Hassan, M J; Leal, S M; Ahmad, W

    2006-09-01

    Congenital alopecia may occur either alone or in association with ectodermal and other abnormalities. On the bases of such associations, several different syndromes featuring congenital alopecia can be distinguished. Alopecia with mental retardation syndrome (APMR) is a rare autosomal recessive disorder, clinically characterized by total or partial hair loss and mental retardation. In the present study, a five-generation Pakistani family with multiple affected individuals with APMR was ascertained. Patients in this family exhibited typical features of APMR syndrome. The disease locus was mapped to chromosome 3q26.2-q26.31 by carrying out a genome scan followed by fine mapping. A maximum two-point logarithm of odds (LOD) score of 2.93 at theta=0.0 was obtained at markers D3S3053 and D3S2309. Multipoint linkage analysis resulted in a maximum LOD score of 4.57 with several markers, which supports the linkage. The disease locus was flanked by markers D3S1564 and D3S2427, which corresponds to 9.6-cM region according to the Rutgers combined linkage-physical map of the human genome (build 35) and contains 5.6 Mb. The linkage interval of the APMR locus identified here does not overlap with the one described previously; therefore, this locus has been designated as APMR2.

  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. Refinement of the locus for non-syndromic sensorineural deafness (DFN2)

    Indian Academy of Sciences (India)

    Bin Cui; Haibing Zhang; Yongzhong Lu; Wei Zhong; Gang Pei; Xiangyin Kong; Landian Hu

    2004-04-01

    Non-syndromic X-linked deafness is a rare form of genetic deafness in humans accounting for a small proportion of all hereditary hearing loss. Different clinical forms of non-syndromic X-linked deafness have been described, and most of these have been mapped. Here, we report a Chinese family affected by a congenital profound sensorineural hearing loss. All phenotypes of this family are clinically compatible with non-syndromic sensorineural deafness (DFN2). A maximum two-point Lod score of 2.32 was obtained at marker DXS6797 ( = 0.00). Recombinants define a region of 4.3 cm flanked by markers DXS6799 and GATA172D05. This region overlaps the previously reported DFN2 region by 2.0 cm.

  7. Chromosome 21 Scan in Down Syndrome Reveals DSCAM as a Predisposing Locus in Hirschsprung Disease

    NARCIS (Netherlands)

    A-S. Jannot (Anne-Sophie); A. Pelet (Anna); A. Henrion-Caude (Alexandra); A. Chaoui (Asma); M. Masse-Morel (Marine); S. Arnold (Stacey); D. Sanlaville (Damien); I. Ceccherini (Isabella); S. Borrego (Salud); R.M.W. Hofstra (Robert); A. Munnich (Arnold); N. Bondurand (Nadège); A. Chakravarti (Aravinda); F. Clerget-Darpoux (Françoise); J. Amiel (Jeanne); S. Lyonnet (Stanislas)

    2013-01-01

    textabstractHirschsprung disease (HSCR) genetics is a paradigm for the study and understanding of multigenic disorders. Association between Down syndrome and HSCR suggests that genetic factors that predispose to HSCR map to chromosome 21. To identify these additional factors, we performed a dose-dep

  8. Evidence that the Saethre-Chotzen syndrome locus lies between D7S664 and D7S507, by genetic analysis and detection of a microdeletion in a patient.

    Science.gov (United States)

    Lewanda, A F; Green, E D; Weissenbach, J; Jerald, H; Taylor, E; Summar, M L; Phillips, J A; Cohen, M; Feingold, M; Mouradian, W

    1994-12-01

    The locus for Saethre-Chotzen syndrome, a common autosomal dominant disorder of craniosynostosis and digital anomalies, was previously mapped to chromosome 7p between D7S513 and D7S516. We used linkage and haplotype analyses to narrow the disease locus to an 8-cM region between D7S664 and D7S507. The tightest linkage was to locus D7S664 (Z = 7.16, theta = .00). Chromosomes from a Saethre-Chotzen syndrome patient with t(2;7) (p23;p22) were used for in situ hybridization with YAC clones containing D7S664 and D7S507. The D7S664 locus was found to lie distal to the 7p22 breakpoint, and the D7S507 locus was deleted from the translocation chromosomes. These genetic and physical mapping data independently show that the disease locus resides in this interval.

  9. Evidence that the Saethre-Chotzen syndrome locus lies between D7S664 and D7S507, by genetic analysis and detection of a microdeletion in a patient

    Energy Technology Data Exchange (ETDEWEB)

    Lewanda, A.F.; Jerald, H.; Taylor, E.; Jabs, E.W. [Johns Hopkins School of Medicine, Baltimore, MD (United States); Green, E.D. [Washington Univ. School of Medicine, St. Louis, MO (United States); Weissenbach, J. [Genethon, Evry (France); Summar, M.L.; Phillips, J.A. III; Cohen, M. [Vanderbilt Univ. School of Medicine, Nashville, TN (United States); Feingold, M. [National Birth Defects Center, Brighton, MA (United States)

    1994-12-01

    The locus for Saethre-Chotzen syndrome, a common autosomal dominant disorder of craniosynostosis and digital anomalies, was previously mapped to chromosome 7p between D7S513 and D7S516. We used linkage and haplotype analyses to narrow the disease locus to an 8-cM region between D7S664 and D7S507. The tightest linkage was to locus D7S664 (Z = 7.16, {theta} = .00). chromosomes from a Saethre-Chotzen syndrome patient with t(2;7) (p23;p22) were used for in situ hybridization with YAC clones containing D7S664 and D7S507. The D7S664 locus was found to lie distal to the 7p22 breakpoint, and the D7S507 locus was deleted from the translocation chromosomes. These genetic and physical mapping data independently show that the disease locus resides in this interval.

  10. 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.

  11. Genetic heterogeneity among craniosynostosis syndromes: mapping the Saethre-Chotzen syndrome locus between D7S513 and D7S516 and exclusion of Jackson-Weiss and Crouzon syndrome loci from 7p.

    Science.gov (United States)

    Lewanda, A F; Cohen, M M; Jackson, C E; Taylor, E W; Li, X; Beloff, M; Day, D; Clarren, S K; Ortiz, R; Garcia, C

    1994-01-01

    Saethre-Chotzen, Crouzon, and Jackson-Weiss syndromes are craniosynostotic autosomal dominant conditions with a wide variability in expression. Saethre-Chotzen has been mapped to chromosome 7p by L. A. Brueton et al. (1992, J. Med. Genet. 29: 681-685), the Greig cephalopolysyndactyly gene was identified at 7p13 by A. Vortkamp et al. (1991, Nature 352: 539-540), and many cases of craniosynostosis have been associated with 7p deletions. We confirmed linkage of the Saethre-Chotzen syndrome locus to chromosome 7p. The tightest linkage was to locus D7S493 (Z = 5.04, theta = 0.00), and linkage and haplotype analyses refined the location of the gene to the region between D7S513 and D7S516. Jackson-Weiss and Crouzon syndrome loci were analyzed using markers spanning the entire 7p arm and were excluded, proving that they are nonallelic to Saethre-Chotzen, Greig cephalopolysyndactyly, and the del(7p) syndromes.

  12. Fine Mapping of a Dravet Syndrome Modifier Locus on Mouse Chromosome 5 and Candidate Gene Analysis by RNA-Seq

    Science.gov (United States)

    Hawkins, Nicole A.; Zachwieja, Nicole J.; Miller, Alison R.; Anderson, Lyndsey L.; Kearney, Jennifer A.

    2016-01-01

    A substantial number of mutations have been identified in voltage-gated sodium channel genes that result in various forms of human epilepsy. SCN1A mutations result in a spectrum of severity ranging from mild febrile seizures to Dravet syndrome, an infant-onset epileptic encephalopathy. Dravet syndrome patients experience multiple seizures types that are often refractory to treatment, developmental delays, and elevated risk for SUDEP. The same sodium channel mutation can produce epilepsy phenotypes of varying clinical severity. This suggests that other factors, including genetic, modify the primary mutation and change disease severity. Mouse models provide a useful tool in studying the genetic basis of epilepsy. The mouse strain background can alter phenotype severity, supporting a contribution of genetic modifiers in epilepsy. The Scn1a+/- mouse model has a strain-dependent epilepsy phenotype. Scn1a+/- mice on the 129S6/SvEvTac (129) strain have a normal phenotype and lifespan, while [129xC57BL/6J]F1-Scn1a+/- mice experience spontaneous seizures, hyperthermia-induced seizures and high rates of premature death. We hypothesize the phenotypic differences are due to strain-specific genetic modifiers that influence expressivity of the Scn1a+/- phenotype. Low resolution mapping of Scn1a+/- identified several Dravet syndrome modifier (Dsm) loci responsible for the strain-dependent difference in survival. One locus of interest, Dsm1 located on chromosome 5, was fine mapped to a 9 Mb region using interval specific congenics. RNA-Seq was then utilized to identify candidate modifier genes within this narrowed region. Three genes with significant total gene expression differences between 129S6/SvEvTac and [129xC57BL/6J]F1 were identified, including the GABAA receptor subunit, Gabra2. Further analysis of Gabra2 demonstrated allele-specific expression. Pharmological manipulation by clobazam, a common anticonvulsant with preferential affinity for the GABRA2 receptor, revealed

  13. Fine Mapping of a Dravet Syndrome Modifier Locus on Mouse Chromosome 5 and Candidate Gene Analysis by RNA-Seq.

    Directory of Open Access Journals (Sweden)

    Nicole A Hawkins

    2016-10-01

    Full Text Available A substantial number of mutations have been identified in voltage-gated sodium channel genes that result in various forms of human epilepsy. SCN1A mutations result in a spectrum of severity ranging from mild febrile seizures to Dravet syndrome, an infant-onset epileptic encephalopathy. Dravet syndrome patients experience multiple seizures types that are often refractory to treatment, developmental delays, and elevated risk for SUDEP. The same sodium channel mutation can produce epilepsy phenotypes of varying clinical severity. This suggests that other factors, including genetic, modify the primary mutation and change disease severity. Mouse models provide a useful tool in studying the genetic basis of epilepsy. The mouse strain background can alter phenotype severity, supporting a contribution of genetic modifiers in epilepsy. The Scn1a+/- mouse model has a strain-dependent epilepsy phenotype. Scn1a+/- mice on the 129S6/SvEvTac (129 strain have a normal phenotype and lifespan, while [129xC57BL/6J]F1-Scn1a+/- mice experience spontaneous seizures, hyperthermia-induced seizures and high rates of premature death. We hypothesize the phenotypic differences are due to strain-specific genetic modifiers that influence expressivity of the Scn1a+/- phenotype. Low resolution mapping of Scn1a+/- identified several Dravet syndrome modifier (Dsm loci responsible for the strain-dependent difference in survival. One locus of interest, Dsm1 located on chromosome 5, was fine mapped to a 9 Mb region using interval specific congenics. RNA-Seq was then utilized to identify candidate modifier genes within this narrowed region. Three genes with significant total gene expression differences between 129S6/SvEvTac and [129xC57BL/6J]F1 were identified, including the GABAA receptor subunit, Gabra2. Further analysis of Gabra2 demonstrated allele-specific expression. Pharmological manipulation by clobazam, a common anticonvulsant with preferential affinity for the GABRA2

  14. Locus of control, perceived parenting style, and symptoms of anxiety and depression in children with Tourette's syndrome.

    Science.gov (United States)

    Cohen, Esther; Sade, Michal; Benarroch, Fortu; Pollak, Yehuda; Gross-Tsur, Varda

    2008-08-01

    This study explored the contribution of two psychosocial factors, locus of control (LOC) and perceived parenting style, to symptoms of internalizing disorders in children with Tourette syndrome (TS). This contribution was further evaluated in relation to TS severity. Sixty-five children (53 boys, 12 girls) ages 9.0-16.9 years, of normal intelligence, completed questionnaires evaluating their depression and anxiety symptoms, LOC, and maternal parenting style. Their mothers rated TS severity, determined by tic severity, symptoms of attention-deficit hyperactivity disorder (ADHD) and obsessive compulsive symptoms (OCS). Higher rates of symptoms of anxiety and depression were associated with a more external LOC and a more rejecting and controlling parenting style. Additionally, depression correlated significantly with tic severity, ADHD and OCS, whereas anxiety correlated only with ADHD symptoms and OCS, but not with tics. Regression analyses showed that LOC, OCS and ADHD symptoms each significantly contributed to predicting anxiety level, whereas LOC and ADHD symptoms significantly contributed to predicting depression symptoms. Rates of symptoms of anxiety and depression in children with TS are markedly influenced by psychosocial factors, extending beyond the influence of ADHD and OCD, both common comorbid disorders in TS. An internal LOC, which is associated with an accepting and autonomy-granting parenting style, appears to be a protective factor against anxiety and depression.

  15. [The cornea: stasis and dynamics].

    Science.gov (United States)

    Nishida, Teruo

    2008-03-01

    The physiological roles of the cornea are to conduct external light into the eye, focus it, together with the lens, onto the retina, and to provide rigidity to the entire eyeball. Good vision thus requires maintenance of the transparency and proper refractive shape of the cornea. Although the cornea appears to be a relatively static structure, dynamic processes operate within and around the cornea at the tissue, cell, and molecular level. In this article, I review the mechanisms responsible for maintenance of corneal homeostasis as well as the development of new modes of treatment for various corneal diseases. I. The static cornea: structure and physiological functions. The cornea is derived from ectoderm, so that it can be considered as transparent skin. It is devoid of blood vessels and manifests the highest sensitivity in the entire body. The surface of the cornea is covered by tear fluid, which serves both as a lubricant and as a conduit for regulatory molecules. The cornea is also supplied with oxygen and various nutrients by the aqueous humor and a loop vascular system in addition to tear fluid. The cornea interacts with its surrounding tissues directly as well as indirectly through tear fluid or aqueous humor, with such interactions playing an important role in the regulation of corneal structure and functions. The resident cells of the cornea-epithelial cells, fibroblasts (keratocytes), and endothelial cells--also engage in mutual interactions through network systems. These interactions as well as those with infiltrated cells and regulation by nerves contribute to the maintenance of the normal structure and functions of the cornea as well as to the repair of corneal injuries. II. The dynamic cornea: maintenance of structure and functions by network systems. Developments in laser and computer technology have allowed observation of the cells and collagen fibers within the cornea. Furthermore, progress in cell and molecular biology has allowed characterization

  16. An Xq22.3 duplication detected by comparative genomic hybridization microarray (Array-CGH) defines a new locus (FGS5) for FG syndrome.

    Science.gov (United States)

    Jehee, Fernanda Sarquis; Rosenberg, Carla; Krepischi-Santos, Ana Cristina; Kok, Fernando; Knijnenburg, Jeroen; Froyen, Guy; Vianna-Morgante, Angela M; Opitz, John M; Passos-Bueno, Maria Rita

    2005-12-15

    FG syndrome is an X-linked multiple congenital anomalies (MCA) syndrome. It has been mapped to four distinct loci FGS1-4, through linkage analysis (Xq13, Xp22.3, and Xp11.4-p11.3) and based on the breakpoints of an X chromosome inversion (Xq11:Xq28), but so far no gene has been identified. We describe a boy with FG syndrome who has an inherited duplication at band Xq22.3 detected by comparative genomic hybridization microarray (Array-CGH). These duplication maps outside all four loci described so far for FG syndrome, representing therefore a new locus, which we propose to be called FGS5. MID2, a gene closely related to MID1, which is known to be mutated in Opitz G/BBB syndrome, maps within the duplicated segment of our patient. Since FG and Opitz G/BBB syndromes share many manifestations we considered MID2 a candidate gene for FG syndrome. We also discuss the involvement of other potential genes within the duplicated segment and its relationship with clinical symptoms of our patient, as well as the laboratory abnormalities found in his mother, a carrier of the duplication.

  17. A locus for Waardenburg syndrome type II maps to chromosome 1p13.3-2.1

    Energy Technology Data Exchange (ETDEWEB)

    Lalwani, A.K.; San Agustin, T.B.; Wilcox, E.R. [LMG, Bethesda, MD (United States)] [and others

    1994-09-01

    Waardenburg syndrome (WS) is a dominantly inherited and clinically variable syndrome of deafness, pigmentary changes and distinctive facial features. WS type I (WS1) is characterized by a high frequency of dystopia canthorum whereas WS type II (WS2) individuals have normal inter canthal distances. Previous studies have shown that WS1 is caused by mutations in the PAX3 gene on chromosome 2q whereas WS2 is unlinked to PAX3. However, analyses of WS2 families have been complicated by the possibility of misdiagnosis of secondary cases with mild features of WS2. We initiated a genome search in 8 WS2 families. Suggestive evidence for linkage to D1S248 and AMY2B was found in one family (both markers: Z-max=2.4 at {Theta}=0), to D1S485 and D1S495 in a second family (both markers: Z-max=2.2 at {Theta}=0), and to D1S248 in a third family (Z-max=1.1 at {Theta}=.11). WS2 was not linked to any of these markers in the total group of families. Location scores for each family were calculated by a six-locus analysis using the marker map AMY2B/D1S486 - .03 - D1S495 - .02 - D1S248 - .05 - D1S457 - .04 - D1S250. Assessment of these scores for linkage and heterogeneity using the admixture test revealed significant evidence for linkage (P<.0001) under the assumption of heterogeneity ({alpha}=.40). The most likely location for WS2 is at D1S495, although either of the intervals flanking this marker may contain the mutant gene. All other locations were ruled out with odds of greater than l00 to 1. Our findings suggest that there are at least two loci for WS type II. Complementary crossovers in the linked families make feasible attempts to narrow the location of the WS2 gene by positional cloning. Analyses of additional families will be needed to estimate more precisely the proportion of linked families and identify the gene.

  18. A new locus for autosomal recessive non-syndromic mental retardation maps to 1p21.1-p13.3.

    Science.gov (United States)

    Uyguner, O; Kayserili, H; Li, Y; Karaman, B; Nürnberg, G; Hennies, Hc; Becker, C; Nürnberg, P; Başaran, S; Apak, M Y; Wollnik, B

    2007-03-01

    Autosomal recessive inheritance of non-syndromic mental retardation (ARNSMR) may account for approximately 25% of all patients with non-specific mental retardation (NSMR). Although many X-linked genes have been identified as a cause of NSMR, only three autosomal genes are known to cause ARNSMR. We present here a large consanguineous Turkish family with four mentally retarded individuals from different branches of the family. Clinical tests showed cognitive impairment but no neurological, skeletal, and biochemical involvements. Genome-wide mapping using Human Mapping 10K Array showed a single positive locus with a parametric LOD score of 4.92 in a region on chromosome 1p21.1-p13.3. Further analyses using polymorphic microsatellite markers defined a 6.6-Mb critical region containing approximately 130 known genes. This locus is the fourth one linked to ARNSMR.

  19. Hemizygosity at the IGF1R locus correlates with growth delay in the ring chromosome 15 syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Peoples, R.; Francke, U. [Stanford Univ., CA (United States)

    1994-09-01

    The ring 15 syndrome is characterized by intrauterine growth retardation, mental retardation, postnatal growth failure, triangular facies, 5th finger clinodactyly, leg-length discrepancy, cafe-au-lait spots and cryptorchidism. The degree of short stature varies from mild to severe and is associated with normal growth hormone and IGF-1 levels, but a wide range of bone age delay. These children retain de novo rings with breakpoints in the short arm at 15p12-11 and in the long arm at 15q26, the region to which the insulin-like growth factor type 1 receptor (IGFIR) has been mapped. We investigated if the degree of growth failure correlates with disruption loss of the IGF1R gene. Ring breakpoints for all patients were determined by typing of RFLP and microsatellite markers from distal 15q for patients and their parents. The order of the loci studied is cen-IVD-FES-D15S130-E15S107-D15S87-D15S86-D15S3. All breakpoints mapped distal to D15S100. Presence or absence of the IGF1R gene on the ring chromsomes of five patients was ascertained by in situ hybridization and gene dosage blots using probes for the more proximally located genes IVD and c-Fes as controls. Heterozygosity for one patient was also confirmed by typing of a polymorphism in the 3{prime} UTR of IGF1R. Two patients who retained the IGF1R were hemizygous at D15S87 while two lacking the IGF1R retained D15S107 indicating that the IGF1R maps between these two markers. Three of the patients with severe growth failure (more than 4 SDs below the mean) were hemizygous at the IGF1R locus while the patient with borderline short stature had two copies of the IGF1R; she was subsequently found to be growth hormone deficient and has demonstrated a response to therapy. Our finding of severe short stature correlating with loss of one copy of the IGF1R suggests a potential role for heterozygous IGF1R mutations in other cases of unexplained growth failure.

  20. Spheroidal Degeneration of the Cornea

    Directory of Open Access Journals (Sweden)

    Erdem Dinç

    2011-08-01

    Full Text Available A thirty-one-year-old male patient presented with bilateral epiphora and stinging sensation in the cornea. Detailed history revealed that a bilateral corneal scraping had been made regarding the initial diagnosis of fungal keratitis. His bestcorrected visual acuities were 20/20 and 20/30 in right and left eyes, respectively. Biomicroscopy showed bilateral amber colored spherules in the anterior stroma of the central cornea. The diagnosis of spheroidal corneal degeneration was established and symptomatic therapy with artificial tear drops was prescribed. Ultraviolet light is widely accepted to be the main etiological factor in the pathogenesis of spheroidal degeneration. Because of difficulties in the early stages of the diagnostic process of the disease, incorrect diagnoses can be made with inappropriate interventions. (Turk J Ophthalmol 2011; 41: 264-6

  1. Bee sting of the cornea.

    Science.gov (United States)

    Singh, G

    1984-04-01

    Irreversible heterochromia-iridis, internal ophthalmoplegia, and punctate subcapsular lenticular opacities developed in a 9-year-old girl after she received a bee sting in her right cornea. These complications persisted even after an 11-month follow-up period. To the author's knowledge, this presentation is the first of its nature. The pathogenesis of these changes is discussed and the literature is reviewed.

  2. Cornea and ocular surface treatment.

    Science.gov (United States)

    De Miguel, Maria P; Alio, Jorge L; Arnalich-Montiel, Francisco; Fuentes-Julian, Sherezade; de Benito-Llopis, Laura; Amparo, Francisco; Bataille, Laurent

    2010-06-01

    In addition to being a protective shield, the cornea represents two thirds of the eye's refractive power. Corneal pathology can affect one or all of the corneal layers, producing corneal opacity. Although full corneal thickness keratoplasty has been the standard procedure, the ideal strategy would be to replace only the damaged layer. Current difficulties in corneal transplantation, mainly immune rejection and shortage of organ supply, place more emphasis on the development of artificial corneas. Bioengineered corneas range from prosthetic devices that solely address the replacement of the corneal function, to tissue-engineered hydrogels that allow regeneration of the tissue. Recently, major advances in the biology of corneal stem cells have been achieved. However, the therapeutic use of these stem cell types has the disadvantage of needing an intact stem cell compartment, which is usually damaged. In addition, long ex vivo culture is needed to generate enough cell numbers for transplantation. In the near future, combination of advanced biomaterials with cells from abundant outer sources will allow advances in the field. For the former, magnetically aligned collagen is one of the most promising ones. For the latter, different cell types will be optimal: 1) for epithelial replacement: oral mucosal epithelium, ear epidermis, or bone marrow- mesenchymal stem cells, 2) for stromal regeneration: adipose-derived stem cells and 3) for endothelial replacement, the possibility of in vitro directed differentiation of adipose-derived stem cells towards endothelial cells provides an exciting new approach.

  3. Narrowing the position of the Treacher Collins syndrome locus to a small interval between three new microsatellite markers at 5q32-33. 1

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, M.J.; Dixon, J. (Univ. of Manchester (United Kingdom)); Houseal, T.; Klinger, K.; Landes, G.M. (Integrated Genetics, Inc., Framingham, MA (United States)); Bhatt, M.; Ward, D.C. (Yale Univ. School of Medicine, New Haven (United States))

    1993-05-01

    Treacher Collins syndrome (TCOF1) is an autosomal dominant disorder of craniofacial development, the features of which include conductive hearing loss and cleft palate. The TCOF1 locus has been localized to chromosome 5q32-33.2. In the present study the authors have used the combined techniques of genetic linkage analysis and fluorescence in situ hybridization (FISH) to more accurately define the TCOF1 critical region. Cosmids IG90 and SPARC, which map to distal 5q, encompass two and one hypervariable microsatellite markers, respectively. The heterozygosity values of these three markers range from .72 to .81. Twenty-two unrelated TCOF1 families have been analyzed for linkage to these markers. There is strong evidence demonstrating linkage to all three markers, the strongest support for positive linkage being provided by haplotyping those markers at the locus encompassed by the cosmid IG90 (Z[sub max]= 19.65; 0 = .010). FISH to metaphase chromosomes and interphase nuclei established that IG90 lies centromeric to SPARC. This information combined with the data generated by genetic linkage analysis demonstrated that the TCOF1 locus is closely flanked proximally by IG90 and distally by SPARC. 30 refs., 2 figs., 4 tabs.

  4. Genetic and physical mapping of the Treacher Collins syndrome locus with respect to loci in the chromosome 5q3 region

    Energy Technology Data Exchange (ETDEWEB)

    Jabs, E.W.; Li, Xiang; Coss, C.; Taylor, E. (Johns Hopkins School of Medicine, Baltimore, MD (United States)); Lovett, M. (Univ. of Texas Southwestern Medical Center, San Antonio, TX (United States)); Yamaoka, L.H.; Speer, M.C. (Duke Univ. Medical Center, Durham, NC (United States)); Cadle, R.; Hall, B. (Univ. of Kentucky, Lexington, KY (United States)); Brown, K. (Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY (United States)) (and others)

    1993-10-01

    Treacher Collins syndrome is an autosomal dominant, craniofacial developmental disorder, and its locus (TCOF1) has been mapped to chromosome 5q3. To refine the location of the gene within this region, linkage analysis was performed among the TCOF1 locus and 12 loci (IL9, FGFA, GRL, D5S207, D5S210, D5S376, CSF1R, SPARC, D5S119, D5S209, D5S527, FGFR4) in 13 Treacher Collins syndrome families. The highest maximum lod score was obtained between loci TCOF1 and D5S210 (Z = 10.52; [theta] = 0.02 [+-] 0.07). The best order, IL9-GRL-D5S207/D5S210-CSF1R-SPARC-D5S119, and genetic distances among these loci were determined in the 40 CEPH families by multipoint linkage analysis. YAC clones were used to establish the order of loci, centromere-5[prime]GRL3[prime]-D5S207-D5S210-D5S376-CSF1R-SPARC-D5S119-telomere. By combining known physical mapping data with ours, the order of chromosome 5q3 markers is centomere-IL9-FGFA-5[prime]GRL3[prime]-D5s207-D5S210-D5S376-CSF1R-SPARC-D5S119-D5S209-FGFR4-telomere. Based on this order, haplotype analysis suggests that the TCOF1 locus resides distal CSF1R and proximal to SPARC within a region less than 1 Mb in size. 29 refs., 2 figs., 2 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.

  6. Synthetic cornea: biocompatibility and optics

    Science.gov (United States)

    Parel, Jean-Marie A.; Kaminski, Stefan; Fernandez, Viviana; Alfonso, E.; Lamar, Peggy; Lacombe, Emmanuel; Duchesne, Bernard; Dubovy, Sander; Manns, Fabrice; Rol, Pascal O.

    2002-06-01

    Purpose. Experimentally find a method to provide a safe surgical technique and an inexpensive and long lasting mesoplant for the restoration of vision in patients with bilateral corneal blindness due to ocular surface and stromal diseases. Methods. Identify the least invasive and the safest surgical technique for synthetic cornea implantation. Identify the most compatible biomaterials and the optimal shape a synthetic cornea must have to last a long time when implanted in vivo. Results. Penetrating procedures were deemed too invasive, time consuming, difficult and prone to long term complications. Therefore a non-penetrating delamination technique with central trephination was developed to preserve the integrity of Descemet's membrane and the anterior segment. Even though this approach limits the number of indications, it is acceptable since the majority of patients only have opacities in the stroma. The prosthesis was designed to fit in the removed tissue plane with its skirt fitted under the delaminated stroma. To improve retention, the trephination wall was made conical with the smallest opening on the anterior surface and a hat-shaped mesoplant was made to fit. The skirt was perforated in its perimeter to allow passage of nutrients and tissues ingrowths. To simplify the fabrication procedure, the haptic and optic were made of the same polymer. The intrastromal biocompatibility of several hydrogels was found superior to current clinically used PMMA and PTFE materials. Monobloc mesoplants made of 4 different materials were implanted in rabbits and followed weekly until extrusion occurred. Some remained optically clear allowing for fundus photography. Conclusions. Hydrogel synthetic corneas can be made to survive for periods longer than 1 year. ArF excimer laser photoablation studies are needed to determine the refractive correction potential of these mesoplants. A pilot FDA clinical trial is needed to assess the mesoplant efficacy and very long-term stability.

  7. Lymphangiogenesis Occurring in Transplanted Corneas

    Institute of Scientific and Technical Information of China (English)

    LING Shiqi; XIAO Qing; HU Yanhua

    2006-01-01

    To study corneal lymphangiogenesis after corneal transplantation, corneal allogenic transplantation models were established in rats. 8 female Wister rats were used as donors, and 16 Sprague Dawley (SD) rats were used as recipients and 2 SD served as controls. Corneal lymphangiogenesis and hemangiogenesis was examined by electron microscopy 1 and 2 weeks after corneal penetrating transplantation, and the expression of lymphatic vessel endothelial receptor (LYVE-1) was examined 1, 3, 7, 14 days after the transplantation respectively. In addition, 19 allograft failed human corneas were examined by 5'-nase-alkaline phosphatase (5'-NA-ALP) doubleenzyme-histochemistry staining to detect corneal lymphangiogenesis and hemangiogenesis. By immunohistochemistry for LYVE-1, it was found that blown lymphatics were localized in the stroma 3days after the corneal transplantation. With electron microscopy, new lymphatic vessels and blood vessels were found 1 and 2 weeks after the corneal transplantation. By 5'-NA-ALP enzyme-histochemistry, corneal hemangiogenesis was found in all allograft failed huma n corneas and 5 of 19(26.3%) cases had developed corneal lymphangiogenesis. It is concluded that corneal lymphangiogenesis is present after corneal transplantation, which may play an important role in allograft rejection.

  8. Gene therapy in the cornea.

    Science.gov (United States)

    Mohan, Rajiv R; Sharma, Ajay; Netto, Marcelo V; Sinha, Sunilima; Wilson, Steven E

    2005-09-01

    Technological advances in the field of gene therapy has prompted more than three hundred phase I and phase II gene-based clinical trials for the treatment of cancer, AIDS, macular degeneration, cardiovascular, and other monogenic diseases. Besides treating diseases, gene transfer technology has been utilized for the development of preventive and therapeutic vaccines for malaria, tuberculosis, hepatitis A, B and C viruses, AIDS, and influenza. The potential therapeutic applications of gene transfer technology are enormous. The cornea is an excellent candidate for gene therapy because of its accessibility and immune-privileged nature. In the last two decades, various viral vectors, such as adeno, adeno-associated, retro, lenti, and herpes simplex, as well as non-viral methods, were examined for introducing DNA into corneal cells in vitro, in vivo and ex vivo. Most of these studies used fluorescent or non-fluorescent marker genes to track the level and duration of transgene expression in corneal cells. However, limited studies were directed to evaluate prospects of gene-based interventions for corneal diseases or disorders such as allograft rejection, laser-induced post-operative haze, herpes simplex keratitis, and wound healing in animal models. We will review the successes and obstacles impeding gene therapy approaches used for delivering genes into the cornea.

  9. Refinement of the Seathre-Chotzen syndrome locus between D7S664 and D7S507 which flank a translocation breakpoint in an affected individual

    Energy Technology Data Exchange (ETDEWEB)

    Lewanda, A.F. [Johns Hopkins Univ., Baltimore, MD (United States)]|[Children`s National Medical Center, Washington, DC (United States); Taylor, E.W.; Jabs, E.W. [Johns Hopkins Univ., Baltimore, MD (United States)] [and others

    1994-09-01

    Saethre-Chotzen syndrome (SCS) is a common autosomal dominant craniosynostosis disorder that has been mapped to distal chromosome 7p. In addition to craniosynostosis, patients with SCS have facial asymmetry, low frontal hairline, ptosis, deviated nasal septum, brachydactyly, and partial cutaneous syndactyly. We evaluated 66 individuals in 10 SCS families. Linkage analysis was performed with 11 dinucleotide repeat markers between D7S513 and D7S516, spanning a genetic distance of 27 cM. The tightest linkage was to marker D7S664 (Z = 7.16, {theta} = 0.00), with a confidence interval of 8 cM. Haplotype analysis of those families with informative recombination events showed the disease locus to lie within the 12 cM region between markers D7S513 and D7S507. We used FISH to physically map the gene using chromosome spreads from the SCS patient with t(2;7)(p23;p22) reported by Reid et al. and YAC clones from a contig spanning the critical interval. These studies confirmed that the breakpoint lies within this region, and in fact identified a microdeletion. Further studies will be targeted towards identification of candidate genes for Saethre-Chotzen syndrome.

  10. 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

    1998-08-01

    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.

  11. Bioengineered Corneas Grafted as Alternatives to Human Donor Corneas in Three High‐Risk Patients

    National Research Council Canada - National Science Library

    Buznyk, Oleksiy; Pasyechnikova, Nataliya; Islam, M. Mirazul; Iakymenko, Stanislav; Fagerholm, Per; Griffith, May

    2015-01-01

    .... In this early observational study, we grafted bioengineered corneal implants made from recombinant human collagen and synthetic phosphorylcholine polymer into three patients for whom donor cornea...

  12. 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.

  13. 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.

  14. Construction of Tissue Engineering Artificial Cornea with Skin Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Yuan LIU; Yan JIN

    2005-01-01

    @@ 1 Introduction The clinical need for an alternative to donor corneal tissue has encouraged much interests in recent years. An artificial cornea must fulfill the functions of the cornea it replaces. More recently, the idea of a bio-engineered cornea has risen. Corneal equivalents have been reconstructed by tissue engineering method. Aim of this study is to construct an artificial rabbit cornea by employing tissue engineering method and to determine if skin stem cells have a role in tissue engineered cornea construction.

  15. Morquio A syndrome-associated mutations: a review of alterations in the GALNS gene and a new locus-specific database.

    Science.gov (United States)

    Morrone, Amelia; Caciotti, Anna; Atwood, Robert; Davidson, Kathryn; Du, Chaoyi; Francis-Lyon, Patricia; Harmatz, Paul; Mealiffe, Matthew; Mooney, Sean; Oron, Tal Ronnen; Ryles, April; Zawadzki, Karl A; Miller, Nicole

    2014-11-01

    Morquio A syndrome (mucopolysaccharidosis IVA) is an autosomal recessive disorder that results from deficient activity of the enzyme N-acetylgalactosamine-6-sulfatase (GALNS) due to alterations in the GALNS gene, which causes major skeletal and connective tissue abnormalities and effects on multiple organ systems. The GALNS alterations associated with Morquio A are numerous and heterogeneous, and new alterations are continuously identified. To aid detection and interpretation of GALNS alterations, from previously published research, we provide a comprehensive and up-to-date listing of 277 unique GALNS alterations associated with Morquio A identified from 1,091 published GALNS alleles. In agreement with previous findings, most reported GALNS alterations are missense changes and even the most frequent alterations are relatively uncommon. We found that 48% of patients are assessed as homozygous for a GALNS alteration, 39% are assessed as heterozygous for two identified GALNS alterations, and in 13% of patients only one GALNS alteration is detected. We report here the creation of a locus-specific database for the GALNS gene (http://galns.mutdb.org/) that catalogs all reported alterations in GALNS to date. We highlight the challenges both in alteration detection and genotype-phenotype interpretation caused in part by the heterogeneity of GALNS alterations and provide recommendations for molecular testing of GALNS.

  16. Mutations at KCNQ1 and an unknown locus cause long QT syndrome in a large Australian family: implications for genetic testing.

    Science.gov (United States)

    Summers, Kim M; Bokil, Nilesh J; Lu, Foong Teng; Low, Jiun Tsuen; Baisden, John M; Duffy, David; Radford, Dorothy J

    2010-03-01

    A large Australian family affected with long QT syndrome (LQTS) was studied. The medical characteristics of the 16 clinically affected members were consistent with LQT1. A previously identified mutation in KCNQ1 was found in 12 affected individuals and 1 unaffected infant but absent in 4 affected family members. A haplotype consisting of specific alleles for microsatellites flanking in KCNQ1 was associated with the mutation. This was absent from the four affected individuals without the mutation, who had three different haplotypes in this region, indicating that LQTS is unlikely to be segregating with KCNQ1 in these anomalous family members. A genome scan revealed 12 regions where all four of these individuals shared alleles. One region on chromosome 21 contained the KCNE1, KCNE2, KCNJ6, and KCNJ15 genes. A common variant of KCNE1 was segregating in the family but did not explain the anomalous cases. A candidate region on chromosome 7 contained the AKAP9 and KCND2 genes. A previously reported mutation in the N-terminal Yotiao region of AKAP9 was absent from the family. No evidence was found implicating any other known or suspected LQTS gene. This family shows that there remain unidentified genetic causes of LQTS which are clinically significant and highlights the difficulties associated with genetic testing in LQTS, since we cannot rule out risk in individuals who are negative for the known mutation in KCNQ1 without knowing the second disease locus.

  17. Localization of the genetic locus for Saethre-Chotzen syndrome to a 6 cM region of chromosome 7 using four cases with apparently balanced translocations at 7p21.2.

    Science.gov (United States)

    Rose, C S; King, A A; Summers, D; Palmer, R; Yang, S; Wilkie, A O; Reardon, W; Malcolm, S; Winter, R M

    1994-08-01

    Saethre-Chotzen syndrome is a common autosomal dominant form of craniosynostosis, which results in the premature fusion of cranial sutures. Craniosynostosis is commonly associated with abnormalities of 7p; Vortkamp et al. (Nature 352, 539-540) demonstrated that the GLI3 gene in 7p13 was disrupted in, patients with Greig syndrome and, more recently, the linkage of genetic markers from 7p with the Saethre-Chotzen syndrome locus has been reported (2,3). Here we report the analysis by fluorescence in situ hybridization of four patients with Saethre-Chotzen syndrome associated with apparently balanced translocations involving band 7p21.2 and different reciprocal chromosomes. We show that in all four patients the breakpoints in 7p are situated within a 6 cM region flanked by the genetic markers D7S488 and D7S493. These results provide further evidence that the genetic locus for Saethre-Chotzen syndrome is located in distal 7p.

  18. Congenital diaphragmatic hernia in Smith-Magenis syndrome: a possible locus at chromosome 17p11.2.

    Science.gov (United States)

    Sanford, E F; Bermudez-Wagner, K; Jeng, L J B; Rauen, K A; Slavotinek, Anne M

    2011-11-01

    We report on a 7-month-old girl with Smith-Magenis syndrome (SMS) due to a 4.76-Mb deletion of 17p12-17p11.2 detected by array comparative genomic hybridization. She was also affected with a left-sided congenital diaphragmatic hernia (CDH) and cardiac anomalies including an atypical atrioventricular canal defect and a cleft mitral valve. To our knowledge, this is the first reported case of a patient with both SMS and CDH. There are numerous chromosomal regions in which duplications, deletions, inversions, or translocations have been associated with CDH, but none have previously been reported at or close to 17p11.2. We discuss candidate genes for the diaphragmatic defect in this patient. Our case demonstrates that it is important to consider the possibility of SMS in non-isolated cases of diaphragmatic hernia.

  19. Investigation of LRTOMT gene (locus DFNB63) mutations in Iranian patients with autosomal recessive non-syndromic hearing loss.

    Science.gov (United States)

    Taghizadeh, Seyyed Hossein; Kazeminezhad, Seyyed Reza; Sefidgar, Seyyed Ali Asghar; Yazdanpanahi, Nasrin; Tabatabaeifar, Mohammad Amin; Yousefi, Ahmad; Lesani, Seyyed Mohammad; Abolhasani, Marziyeh; Hashemzadeh Chaleshtori, Morteza

    2013-01-01

    Hearing loss (HL) is the most frequent sensory defect affecting 1 in 1000 neonates. This can occur due to genetic or environmental causes or both. The genetic causes are very heterogenous and over 100 loci have been identified to cause autosomal recessive non - syndromic hearing loss (ARNSHL). The aim of this study was to determine the contribution of the LRTOMT gene mutations in causing ARNSHL. One hundred fifty seven pupils affected with ARNSHL from Azarbaijan Sharghi, Kordestan, Gilan and Golestan provinces, north and west of Iran, were ascertained. In this descriptive - laboratory study, the presence of LRTOMT mutations were initially checked using PCR - Single - strand conformation polymorphism (SSCP) and heteroduplex analysis (HA) strategy. Samples with shifted bands on the gel were confirmed by DNA sequencing method. The PCR-SSCP/HA and the subsequent direct DNA sequencing showed no mutation in the population studied. We conclude that LRTOMT mutations have no role in causing sporadic deafness in the studied population. Further studies on other populations and samples could clarify the exact role of LRTOMT mutations.

  20. C8orf37 is mutated in Bardet-Biedl syndrome and constitutes a locus allelic to non-syndromic retinal dystrophies.

    Science.gov (United States)

    Khan, Arif O; Decker, Eva; Bachmann, Nadine; Bolz, Hanno J; Bergmann, Carsten

    2016-09-01

    Bardet-Biedl syndrome (BBS) is a pleiotropic and clinically and genetically heterogeneous ciliopathy. Primary features are early-onset retinal dystrophy that is typically rod-cone, obesity, polydactyly, renal abnormalities, hypogonadism, and learning difficulties, but most patients do not present with the full clinical picture. In a BBS patient from a consanguineous marriage we performed next-generation sequencing targeting all known BBS genes and other genes known or hypothesized to cause ciliopathies. While no mutation was present in any of the recognized genes for BBS, we were able to identify the homozygous non-conservative mutation c.529C>T (p.Arg177Trp) in C8orf37 that segregated with the phenotype, affects an evolutionarily highly conserved residue, and is bioinformatically predicted to be pathogenic. The same mutation has been described in unrelated patients with non-syndromic cone-rod dystrophy and other C8orf37 changes were found in individuals with retinitis pigmentosa. We conclude that C8orf37 should be added to BBS screening panels as a probable rare cause of the disease and that individuals with C8orf37-related retinal dystrophy should be screened for BBS features.

  1. Designing a perfect cornea: computational aspects

    Science.gov (United States)

    Rubinstein, Jacob; Wolansky, Gershon

    2002-12-01

    We analyze an algorithm for the design of a perfect cornea that exactly focuses a preselected object or a preselected wave front on the retina. The algorithm can be used, for example, in refractive surgery. We consider the sensitivity of the algorithm to various errors, including errors in the measurements of the aberrations, the original corneal topography and the ablation process.

  2. 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

  3. Construction of Tissue Engineering Artificial Cornea with Skin Stem Cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionThe clinical need for an alternative to donor corneal tissue has encouraged much interests in recent years. An artificial cornea must fulfill the functions of the cornea it replaces. More recently, the idea of a bio-engineered cornea has risen. Corneal equivalents have been reconstructed by tissue engineering method. Aim of this study is to construct an artificial rabbit cornea by employing tissue engineering method and to determine if skin stem cells have a role in tissue engineered cornea co...

  4. Use of corneas for transplant after self-inflicted eyeballs enucleation in the Italian law.

    Science.gov (United States)

    Montanari Vergallo, G; Pacella, E; Di Luca, A; Di Luca, N M; Cecchi, R; Marinelli, E

    2017-01-01

    The authors analyze from an ethical and legal point of view the case of a 37 year old man, hospitalized for four days because of a 'dissociative syndrome', who had introduced in both his orbits a portable radio antenna. Most likely, he completed the self-enuclation using his own hands. He was brought to the Ophtalmic Hospital by nurses who handed the two eyeballs to the physicians who ascertained that the corneas were intact. Then, they performed the conservative extraction. In the following days those corneas were transplanted (keratoplasty) on two subjects on the waiting list at that hospital. The case raises the question of whether it is lawful and ethically acceptable to take, for transplant use, the corneas of a mentally incapable patient who has excised his own eyeballs. The authors analyze the case from the angle of the Italian law and Oviedo Convention. Neither of them has a specific regulation on this topic. It is therefore necessary to apply general principles that holdvalidfor Italy and a variety of countries worldwide. Particularly, the choice to use the corneas for transplant did not prejudice the physical integrity of the patient, who could no longer utilize his own eyeballs. His self-determination has not been affected; in fact, he was not in the position to make a conscious decision. Additionally, the so-called "implied consent" could be applied. Therefore, the principle of human solidarity, which is the moral duty to benefit others, seems to prevail in the case at hand.

  5. 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

    2017-03-21

    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.

  6. [Effect of phacoemulsification on the cornea].

    Science.gov (United States)

    Stănilă, D M; Stănilă, Adriana; Mihai, Elena; Sîrbu, N G; Stupariu, A L

    2013-01-01

    Cataracta is the more common surgical diesease of the eye. The removal of the cataract is done my phacoemulsification. To evaluate the effect of phacoemulsifcation on the cornea. We have studied 80 patients with cataract that underwent cataract surgery by phacoemulsification. We measured the corneal thickness and the number of endothelial cell before and after the surgery. REZULTS AND DISCUSSIONS: Corneal thickness grew with 3% and the number of endothelial cells decresed with 13%. Phacoemulsification with the use of vascoelastic substancees is a very safe method of lens extraction

  7. Awareness of Cornea Donation of Registered Tissue Donors in Nanjing

    Institute of Scientific and Technical Information of China (English)

    Ting Chu; Lin-nong Wang; Hao Yu; Ru-yang Zhang

    2013-01-01

    Objective To evaluate the current cornea donation awareness of tissue donors in the city of Nanjing,China. Methods Altogether 2000 registered tissue donors in the Red Cross Eye Bank of Nanjing by the end of 2010 and 2000 control residents of Nanjing in February to June 2011 were randomly selected to par-ticipate in our field questionnaire survey. The questionnaire consisted of questions regarding the understand-ing of cornea donation,the attitude toward cornea donation,and attitude toward legislation and free dona-tion. The awareness of cornea donation between the registered tissue donors and residents was compared. Related factors of the willingness to donate corneas and to become a tissue donor were evaluated with uni-variate and multiple logistic regression analysis. Results A total of 1867 (response rate: 93.4%) tissue donors and 1796 (response rate: 89.8%; ef-fective questionnaires: 1697) residents participated in this survey. For the questions about the knowledge of cornea donation,90.3% tissue donors (residents: 78.9%) knew that donated corneas could be used for transplantations; 71.2% tissue donors (residents: 47.6%) knew that the appearance would not be destroyed after cornea donation; 70.7% tissue donors (residents: 20.0%) knew the formalities to become a cornea do-nor. For attitude toward cornea donation,82.2% tissue donors (residents: 45.1%) were willing to donate corneas or eyeballs after death; 84.0% tissue donors (residents: 30.2%) had discussed with their families about donation; 85.1% tissue donors (residents: 24.8%) supported their families' or friends' cornea donation. For attitude toward legislation and free donation,88.3% tissue donors (residents: 61.3%) approved of legis-lation to regular cornea donation; 72.2% tissue donors (residents: 38.8%) thought that cornea or organ do-nation should be gratis. The difference between two groups was significant (P<0.001). However,some tissue donors did not know cornea donation well,some even opposed the

  8. Investigation of Friction-induced Damage to the Pig Cornea

    NARCIS (Netherlands)

    da Cruz Barros, Raquel; Van Kooten, Theo G.; Veeregowda, Deepak Halenahally

    2015-01-01

    Mechanical friction causes damage to the cornea. A friction measurement device with minimal intervention with the pig cornea tear film revealed a low friction coefficient of 0.011 in glycerine solution. Glycerine molecules presumably bind to water, mucins, and epithelial cells and therewith improve

  9. Investigation of Friction-induced Damage to the Pig Cornea

    NARCIS (Netherlands)

    da Cruz Barros, Raquel; Van Kooten, Theo G.; Veeregowda, Deepak Halenahally

    2015-01-01

    Mechanical friction causes damage to the cornea. A friction measurement device with minimal intervention with the pig cornea tear film revealed a low friction coefficient of 0.011 in glycerine solution. Glycerine molecules presumably bind to water, mucins, and epithelial cells and therewith improve

  10. 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.

  11. Estimation of the surface tension of ocular cornea

    Science.gov (United States)

    Zhang, Xueyong; Ma, Jianguo; Lu, Rongsheng; Xia, Ruixue

    2008-12-01

    Considering the potential clinical importance, the surface tension of ocular cornea under the action of normal physiological intraocular pressure is estimated, and a novel technique and a simple mechanical model for determining the tension are also presented in this paper. An instrument embodying mainly a CCD camera, an optical staff gauge and a manometer was developed primarily to measure both the surface point displacement and intraocular pressure of the cornea. A simple theoretical model was used to characterize the tensions of the ocular corneas under the action of the intraocular pressure. Due to the difficulty in obtaining the human cornea, laboratory experiments were carried out on porcine cornea specimens. The thickness of the specimens was accurately measured by optical coherence tomography. The matrix and collagen properties within the corneal tissue were manifested in the experiment. Experimental results on porcine corneas showed that the present technique is applicable to estimate the surface tension. In the normal physiological intraocular pressure range, both meridian and circumference tensions of the porcine corneas along the radial coordinate distribute are not uniform.

  12. 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

    . RESULTS. Fibrillar deposits of an antiadhesive glycoprotein tenascin in the anterior and posterior stroma, epithelial basement membrane (BM), bullae and subepithelial fibrosis (SEF) areas, and posterior collagenous layer (PCL) were revealed in disease corneas. Tenascin in midstroma, which was observed...

  13. 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.

  14. Measurement of the anisotropic thermal conductivity of the porcine cornea.

    Science.gov (United States)

    Barton, Michael D; Trembly, B Stuart

    2013-10-01

    Accurate thermal models for the cornea of the eye support the development of thermal techniques for reshaping the cornea and other scientific purposes. Heat transfer in the cornea must be quantified accurately so that a thermal treatment does not destroy the endothelial layer, which cannot regenerate, and yet is responsible for maintaining corneal transparency. We developed a custom apparatus to measure the thermal conductivity of ex vivo porcine corneas perpendicular to the surface and applied a commercial apparatus to measure thermal conductivity parallel to the surface. We found that corneal thermal conductivity is 14% anisotropic at the normal state of corneal hydration. Small numbers of ex vivo feline and human corneas had a thermal conductivity perpendicular to the surface that was indistinguishable from the porcine corneas. Aqueous humor from ex vivo porcine, feline, and human eyes had a thermal conductivity nearly equal to that of water. Including the anisotropy of corneal thermal conductivity will improve the predictive power of thermal models of the eye. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A nonsense mutation in CEP55 defines a new locus for a Meckel-like syndrome, an autosomal recessive lethal fetal ciliopathy.

    Science.gov (United States)

    Bondeson, M-L; Ericson, K; Gudmundsson, S; Ameur, A; Pontén, F; Wesström, J; Frykholm, C; Wilbe, M

    2017-11-01

    Mutations in genes involved in the cilium-centrosome complex are called ciliopathies. Meckel-Gruber syndrome (MKS) is a ciliopathic lethal autosomal recessive syndrome characterized by genetically and clinically heterogeneous manifestations, including renal cystic dysplasia, occipital encephalocele and polydactyly. Several genes have previously been associated with MKS and MKS-like phenotypes, but there are still genes remaining to be discovered. We have used whole-exome sequencing (WES) to uncover the genetics of a suspected autosomal recessive Meckel syndrome phenotype in a family with 2 affected fetuses. RNA studies and histopathological analysis was performed for further delineation. WES lead to identification of a homozygous nonsense mutation c.256C>T (p.Arg86*) in CEP55 (centrosomal protein of 55 kDa) in the affected fetus. The variant has previously been identified in carriers in low frequencies, and segregated in the family. CEP55 is an important centrosomal protein required for the mid-body formation at cytokinesis. Our results expand the list of centrosomal proteins implicated in human ciliopathies and provide evidence for an essential role of CEP55 during embryogenesis and development of disease. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Portable light transmission measuring system for preserved corneas

    Science.gov (United States)

    Ventura, Liliane; de Jesus, Gabriel Torres; de Oliveira, Gunter Camilo Dablas; Sousa, Sidney JF

    2005-01-01

    Background The authors have developed a small portable device for the objective measurement of the transparency of corneas stored in preservative medium, for use by eye banks in evaluation prior to transplantation. Methods The optical system consists of a white light, lenses, and pinholes that collimate the white light beams and illuminate the cornea in its preservative medium, and an optical filter (400–700 nm) that selects the range of the wavelength of interest. A sensor detects the light that passes through the cornea, and the average corneal transparency is displayed. In order to obtain only the tissue transparency, an electronic circuit was built to detect a baseline input of the preservative medium prior to the measurement of corneal transparency. The operation of the system involves three steps: adjusting the "0 %" transmittance of the instrument, determining the "100 %" transmittance of the system, and finally measuring the transparency of the preserved cornea inside the storage medium. Results Fifty selected corneas were evaluated. Each cornea was submitted to three evaluation methods: subjective classification of transparency through a slit lamp, quantification of the transmittance of light using a corneal spectrophotometer previously developed, and measurement of transparency with the portable device. Conclusion By comparing the three methods and using the expertise of eye bank trained personnel, a table for quantifying corneal transparency with the new device has been developed. The correlation factor between the corneal spectrophotometer and the new device is 0,99813, leading to a system that is able to standardize transparency measurements of preserved corneas, which is currently done subjectively. PMID:16372912

  17. Methylation at the PW71 locus on chromosome 15 in DNA derived from CVS and from amniocytes; implications for the use of the PW71 probe in prenatal diagnosis of the Prader-Willi and Angleman syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Telleria, P.; Yu, C.C.; Brown, S. [Columbia Univ., New York, NY (United States)

    1994-09-01

    The probe PW71 spans a HpaII site in the Prader-Willi/Angleman Syndrome critical region on chromosome 15. A single Southern blot with this probe can be used to detect deletion and uniparental disomy. We attempted to determine the methylation state of the PW71 locus in DNA derived from prenatal sources. Southern blots of HindIII and HindIII/HpaII double digests of DNA from cultured amniocytes and CVS specimens were prepared and probed with the PW71 probe. The results from 6 cultured CVS specimens indicate that several HPAII sites recognized by the PW71 probe are not methylated in trophoblast. Four amniotic fluid cultures gave results which were not different from lymphocyte-derived DNA; however, in several cases, amniotic fluid cultures resulted in Southern blots identical to those from CVS. Since we did not have verified prenatal cases of chromosome 15 uniparental disomy, we were unable to determine whether the parent-of-origin specific methylation present in lymphocyte DNA is also present in amniocyte DNA. We conclude that prenatal determination of chromosome 15 uniparental disomy with this probe will be unreliable.

  18. Nerve repulsion by the lens and cornea during cornea innervation is dependent on Robo-Slit signaling and diminishes with neuron age.

    Science.gov (United States)

    Schwend, Tyler; Lwigale, Peter Y; Conrad, Gary W

    2012-03-01

    The cornea, the most densely innervated tissue on the surface of the body, becomes innervated in a series of highly coordinated developmental events. During cornea development, chick trigeminal nerve growth cones reach the cornea margin at embryonic day (E)5, where they are initially repelled for days from E5 to E8, instead encircling the corneal periphery in a nerve ring prior to entering on E9. The molecular events coordinating growth cone guidance during cornea development are poorly understood. Here we evaluated a potential role for the Robo-Slit nerve guidance family. We found that Slits 1, 2 and 3 expression in the cornea and lens persisted during all stages of cornea innervation examined. Robo1 expression was developmentally regulated in trigeminal cell bodies, expressed robustly during nerve ring formation (E5-8), then later declining concurrent with projection of growth cones into the cornea. In this study we provide in vivo and in vitro evidence that Robo-Slit signaling guides trigeminal nerves during cornea innervation. Transient, localized inhibition of Robo-Slit signaling, by means of beads loaded with inhibitory Robo-Fc protein implanted into the developing eyefield in vivo, led to disorganized nerve ring formation and premature cornea innervation. Additionally, when trigeminal explants (source of neurons) were oriented adjacent to lens vesicles or corneas (source of repellant molecules) in organotypic tissue culture both lens and cornea tissues strongly repelled E7 trigeminal neurites, except in the presence of inhibitory Robo-Fc protein. In contrast, E10 trigeminal neurites were not as strongly repelled by cornea, and presence of Robo-Slit inhibitory protein had no effect. In full, these findings suggest that nerve repulsion from the lens and cornea during nerve ring formation is mediated by Robo-Slit signaling. Later, a shift in nerve guidance behavior occurs, in part due to molecular changes in trigeminal neurons, including Robo1 downregulation

  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. Biomechanical Measurement of Rabbit Cornea by a Modified Scheimpflug Device

    Science.gov (United States)

    Zhang, Bo; Gu, Jianjun; Zhang, Xiaoxiao; Yang, Bin

    2016-01-01

    Purpose. To explore the probability and variation in biomechanical measurements of rabbit cornea by a modified Scheimpflug device. Methods. A modified Scheimpflug device was developed by imaging anterior segment of the model imitating the intact eye at various posterior pressures. The eight isolated rabbit corneas were mounted on the Barron artificial chamber and images of the anterior segment were taken at posterior pressures of 15, 30, 45, 60, and 75 mmHg by the device. The repeatability and reliability of the parameters including CCT, ACD, ACV, and CV were evaluated at each posterior pressure. All the variations of the parameters at the different posterior pressures were calculated. Results. All parameters showed good intraobserver reliability (Cronbach's alpha; intraclass correlation coefficient, α, ICC > 0.96) and repeatability in the modified Scheimpflug device. With the increase of posterior pressures, the ratio of CCT decreased linearly and the bulk modulus gradually reduced to a platform. The increase of ACD was almost linear with the posterior pressures elevated. Conclusions. The modified Scheimpflug device was a valuable tool to investigate the biomechanics of the cornea. The posterior pressure 15–75 mmHg range produced small viscoelastic deformations and nearly linear pressure-deformation response in the rabbit cornea. PMID:27446608

  1. 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 ...

  2. 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 ...

  3. 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 ...

  4. 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 ...

  5. Calcareous degeneration of the canine cornea.

    Science.gov (United States)

    Sansom, Jane; Blunden, Tony

    2010-07-01

    The purpose of this paper is to describe a specific presentation of canine corneal calcification. Fourteen cases are described. In seven cases the corneal lesions were bilaterally symmetrical. In five cases the corneal lesion was unilateral. Two dogs were uniocular, the contralateral eye had been enucleated between 1 and 3 months previously by the referring veterinary surgeon following corneal ulceration and perforation. Of a total of 21 eyes with corneal calcification, 16 eyes had associated ulceration. The ulceration presented as follows: two eyes had descemetocoeles, four eyes had corneal perforations, eight eyes had stromal ulceration, and two eyes had superficial punctate ulceration. The cause of the corneal mineralization remains undetermined but underlying systemic disease, particularly hyperadrenocorticism (Cushing's Syndrome), is suspected as a possible contributing factor in some of these cases. Histopathology was carried out on three cases following a keratectomy and placement of a conjunctival pedicle flap into the ulcerated lesion.

  6. The transparent lens and cornea in the mouse and zebra fish eye.

    Science.gov (United States)

    Greiling, Teri M S; Clark, John I

    2008-04-01

    The lens and cornea combine to form a single optical element in which transparency and refraction are the fundamental biophysical characteristics required for a functional visual system. Although lens and cornea have different cellular and extracellular specializations that contribute to transparency and refraction, their development is closely related. In the embryonic mouse, the developing cornea and lens separate early. In contrast, zebra fish lens and cornea remain connected during early development and the optical properties of the cornea and lens observed by slit lamp and quasielastic laser light scattering spectroscopy (QLS) are more similar in the zebra fish eye than in the mouse eye. Optical similarities between cornea and lens of zebra fish may be the result of similarities in the cellular development of the cornea and lens.

  7. Acanthamoeba castellanii: morphological analysis of the interaction with human cornea.

    Science.gov (United States)

    Omaña-Molina, Maritza; González-Robles, Arturo; Salazar-Villatoro, Lizbeth Iliana; Cristóbal-Ramos, Ana Ruth; González-Lázaro, Mónica; Salinas-Moreno, Edmundo; Méndez-Cruz, Rene; Sánchez-Cornejo, Manuel; De la Torre-González, Enrique; Martínez-Palomo, Adolfo

    2010-09-01

    The present study demonstrates that when Acanthamoeba castellanii trophozoites are co-cultivated with isolated human corneas, the amoeba can be invasive and cause damage to the intact corneal epithelium without the requirement of previous corneal abrasion. After adhesion, A. castellanii trophozoites migrate between cells forming bumps on the corneal cell layers and reaching Bowman s membrane in 3h, although no evidence of cell damage was observed until the phagocytic process was detected. Likewise, conditioned medium produced damage to the corneal cells that was proportional to the time of incubation, but this cytophatic effect involved only the most superficial layer of the human cornea and was not enough to explain amoebic invasion of Bowman s membrane. As a result of our observations, we suggest that the mechanical action of the trophozoites and phagocytosis of corneal cells during the process of corneal invasion are more important than previously suggested.

  8. Posterior polymorphous dystrophy of the cornea. An ultrastructural study.

    Science.gov (United States)

    de Felice, G P; Braidotti, P; Viale, G; Bergamini, F; Vinciguerra, P

    1985-01-01

    A corneal button excised from a 2-month-old infant with congenital posterior polymorphous dystrophy of the cornea, a rare disease affecting Descemet's membrane and endothelium, was examined by electron microscopy. We observed irregularly arranged, sometimes multilayered cells with marked epithelial features, lining the posterior surface of the cornea in place of the endothelium, and Descemet's membrane with focal alterations sometimes involving all of its layers. We interpreted these abnormal cells as epithelial-like cells. As these findings were in a very young patient, which is unusual, we concluded that the onset of the disease may take place in the early period of intrauterine life, corresponding to the beginning of Descemet's membrane production.

  9. Live imaging of newly formed lymphatic vessels in the cornea

    Institute of Scientific and Technical Information of China (English)

    Don Yuen; Xiufeng Wu; Alex C Kwan; Jeffrey LeDue; Hui Zhang; Tatiana Ecoiffier; Bronislaw Pytowski; Lu Chen

    2011-01-01

    Dear Editor,Lymphatic research denotes a field of new discovery and has experienced exponential growth in recent years [1-3].Though lymphatic dysfunction has been found in a broad spectrum of disorders from transplant rejection to cancer metastasis,to date,there is still little effective treatment for lymphatic diseases,so it is a field with urgent demand for new experimental approaches and therapeutic protocols.The cornea provides an ideal site for lymphatic research due to its accessible location,transparent nature,and alymphatic status under normal condition [2,4].Indeed,the use of this tissue for tumor angiogenesis research dates back to 1970s [5].Most recently,we have demonstrated that the cornea possesses a full range of plasticity in lymphatic formation and regression [6].An advanced technology for live imaging of lymphatic vessels in this tissue would therefore have widespread applications in biomedical research.

  10. Why does the healthy cornea resist Pseudomonas aeruginosa infection?

    Science.gov (United States)

    Evans, David J; Fleiszig, Suzanne M J

    2013-06-01

    To provide our perspective on why the cornea is resistant to infection based on our research results with Pseudomonas (P) aeruginosa. We focus on our current understanding of the interplay between bacteria, tear fluid, and the corneal epithelium that determines 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. 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 survives at the ocular surface, adheres, and traverses multilayered corneal epithelia. These models also help elucidate the molecular mechanisms of corneal epithelial innate defense. 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 III secretion system, proteases, and P aeruginosa biofilm formation on contact lenses. After more than 2 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. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Neuronal Changes in the Diabetic Cornea: Perspectives for Neuroprotection

    Science.gov (United States)

    Yamamoto, Shuichi

    2016-01-01

    Diabetic neuropathy is associated with neurotrophic ulcerations of the skin and cornea. Decreased corneal sensitivity and impaired innervation lead to weakened epithelial wound healing predisposing patients to ocular complications such as corneal infections, stromal opacification, and surface irregularity. This review presents recent findings on impaired corneal innervation in diabetic individuals, and the findings suggest that corneal neuropathy might be an early indicator of diabetic neuropathy. Additionally, the recent findings for neuroprotective and regenerative therapy for diabetic keratopathy are presented. PMID:28044131

  12. Management of chemical burns of the canine cornea

    OpenAIRE

    Christmas, Richard

    1991-01-01

    Significant clinical signs and general principles of treatment for chemical burns of the canine cornea are presented using three typical case studies for illustration. Alkali burns are more common in dogs than acid burns. The sources of alkali in this study were soap, cement, and mortar dust. Common signs of chemical burns are ocular pain, corneal ulceration, tear film inadequacy, corneal edema, and marked corneal neovascularity. Successful treatment requires thorough ocular lavage, treatment...

  13. [Temporary biokeratoprostheses in total destruction of the cornea].

    Science.gov (United States)

    Onishchenko, A L; Kolbasko, A V; Kramer, E R

    2016-01-01

    The paper presents an original method for temporary biokeratoprothetics in total destruction of the cornea, which consists of the following. In the operating room a 12-mm disc is cut out of patient's conchal cartilage by a trephine and then thinned down to 1 mm with a blade. The prepared autograft is placed in front of the iris completely overlapping corneal defect and sutured to the sclera with 10--12 U-shaped interrupted stitches using a 7/0 suture. Between the stitches 0.2--0.3 ml of viscoelastic are injected into the anterior chamber. Temporary blepharorrhaphy is done within the temporal one-third of the eyelids with a U-shaped suture 6/0. The authors present an own clinical observation of patient D., aged 46, with purulent corneal ulcer and total destruction of the cornea. In ophthalmic emergency, if no donor cornea is available, the described method allows to save the eyeball from its anatomical and functional loss. Further routine keratoplasty or optical keratoprosthetics may bring some functional improvement.

  14. Ultrahigh-resolution OCT imaging of the human cornea

    Science.gov (United States)

    Werkmeister, René M.; Sapeta, Sabina; Schmidl, Doreen; Garhöfer, Gerhard; Schmidinger, Gerald; Aranha dos Santos, Valentin; Aschinger, Gerold C.; Baumgartner, Isabella; Pircher, Niklas; Schwarzhans, Florian; Pantalon, Anca; Dua, Harminder; Schmetterer, Leopold

    2017-01-01

    We present imaging of corneal pathologies using optical coherence tomography (OCT) with high resolution. To this end, an ultrahigh-resolution spectral domain OCT (UHR-OCT) system based on a broad bandwidth Ti:sapphire laser is employed. With a central wavelength of 800 nm, the imaging device allows to acquire OCT data at the central, paracentral and peripheral cornea as well as the limbal region with 1.2 µm x 20 µm (axial x lateral) resolution at a rate of 140 000 A-scans/s. Structures of the anterior segment of the eye, not accessible with commercial OCT systems, are visualized. These include corneal nerves, limbal palisades of Vogt as well as several corneal pathologies. Cases such as keratoconus and Fuchs’s endothelial dystrophy as well as infectious changes caused by diseases like Acanthamoeba keratitis and scarring after herpetic keratitis are presented. We also demonstrate the applicability of our system to visualize epithelial erosion and intracorneal foreign body after corneal trauma as well as chemical burns. Finally, results after Descemet’s membrane endothelial keratoplasty (DMEK) are imaged. These clinical cases show the potential of UHR-OCT to help in clinical decision-making and follow-up. Our results and experience indicate that UHR-OCT of the cornea is a promising technique for the use in clinical practice, but can also help to gain novel insight in the physiology and pathophysiology of the human cornea. PMID:28271013

  15. 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.

  16. Evaluation of corneal cell growth on tissue engineering materials as artificial cornea scaffolds

    Directory of Open Access Journals (Sweden)

    Hai-Yan Wang

    2013-12-01

    Full Text Available The keratoprosthesis (KPro; artificial cornea is a special refractive device to replace human cornea by using heterogeneous forming materials for the implantation into the damaged eyes in order to obtain a certain vision. The main problems of artificial cornea are the biocompatibility and stability of the tissue particularly in penetrating keratoplasty. The current studies of tissue-engineered scaffold materials through comprising composites of natural and synthetic biopolymers together have developed a new way to artificial cornea. Although a wide agreement that the long-term stability of these devices would be greatly improved by the presence of cornea cells, modification of keratoprosthesis to support cornea cells remains elusive. Most of the studies on corneal substrate materials and surface modification of composites have tried to improve the growth and biocompatibility of cornea cells which can not only reduce the stimulus of heterogeneous materials, but also more importantly continuous and stable cornea cells can prevent the destruction of collagenase. The necrosis of stroma and spontaneous extrusion of the device, allow for maintenance of a precorneal tear layer, and play the role of ensuring a good optical surface and resisting bacterial infection. As a result, improvement in corneal cells has been the main aim of several recent investigations; some effort has focused on biomaterial for its well biological properties such as promoting the growth of cornea cells. The purpose of this review is to summary the growth status of the corneal cells after the implantation of several artificial corneas.

  17. Proteinases of the cornea and preocular tear film.

    Science.gov (United States)

    Ollivier, F J; Gilger, B C; Barrie, K P; Kallberg, M E; Plummer, C E; O'Reilly, S; Gelatt, K N; Brooks, D E

    2007-01-01

    Maintenance and repair of corneal stromal extracellular matrix (ECM) requires a tightly coordinated balance of ECM synthesis, degradation and remodeling in which proteolytic enzymes (proteinases) perform important functions. There are natural proteinase inhibitors present in preocular tear film (PTF) and cornea simultaneously with proteinases that prevent excessive degradation of normal healthy tissue. Disorders occur when there is an imbalance between proteinases and proteinase inhibitors in favor of the proteinases, causing pathologic degradation of stromal collagen and proteoglycans in the cornea. Two matrix metalloproteinases (MMPs), MMP-2 and MMP-9, are of major importance in terms of remodeling and degradation of the corneal stromal collagen. Immunohistochemical studies have shown different origins of MMP-2 and -9. MMP-2 is synthesized by corneal keratocytes and performs a surveillance function in the normal cornea, becoming locally activated to degrade collagen molecules that occasionally become damaged. Alternatively, MMP-9 may be produced by epithelial cells and polymorphonuclear neutrophils following corneal wounding. Because the cornea is in close contact with the preocular tear film (PTF), proteinases have been evaluated in the PTF. In damaged corneas, total proteolytic activity in the tear fluid was found to be significantly increased compared to normal eyes and contralateral eyes. Studies analyzing the proteolytic activity in serial PTF samples during corneal healing led to the following conclusions: ulcerative keratitis in animals is associated with initially high levels of tear film proteolytic activity, which decrease as ulcers heal; proteinase levels in melting ulcers remain elevated leading to rapid progression of the ulcers. The success of medical and surgical treatment of the corneal ulcers is reflected by the proteolytic activity in tears. In animals, successful treatment leads to a rapid reduction in tear film proteolytic activity that

  18. Eliana Machado, Locus Brasilis

    OpenAIRE

    Ramos, Domingo

    2013-01-01

    Locus Brasilis es un complejo libro de la poeta brasileña y trilingüe Eliana Machado, que actualmente radica en Europa y por primera vez publica en el Perú. El volumen, el segundo de la autora luego de Blanco en el blanco, que apareció en Sao Paulo, consta de tres partes bien definidas, que corresponden a los tres reinos de la naturaleza. En poesía esto se traslada al hombre con sus respectivos correlatos del animal como ser destructivo, pero también conciliador y hasta protector de un mundo ...

  19. Is the novel SCKL3 at 14q23 the predominant Seckel locus?

    Science.gov (United States)

    Kilinç, Mehmet Okyay; Ninis, Vasiliki Ninidu; Ugur, Sibel Aylin; Tüysüz, Beyhan; Seven, Mehmet; Balci, Sevim; Goodship, Judith; Tolun, Aslihan

    2003-11-01

    Seckel syndrome (SCKL) is a rare disease with wide phenotypic heterogeneity. A locus (SCKL1) has been identified at 3q and another (SCKL2) at 18p, both in single kindreds afflicted with the syndrome. We report here a novel locus (SCKL3) at 14q by linkage analysis in 13 Turkish families. In total, 18 affected and 10 unaffected sibs were included in the study. Of the 10 informative families, nine with parental consanguinity and one reportedly nonconsanguineous but with two affected sibs, five were indicative of linkage to the novel locus. One of those families also linked to the SCKL1 locus. A consanguineous family with one affected sib was indicative of linkage to SCKL2. The novel gene locus SCKL3 is 1.18 cM and harbors ménage a trois 1, a gene with a role in DNA repair.

  20. The Ets transcription factor EHF as a regulator of cornea epithelial cell identity.

    Science.gov (United States)

    Stephens, Denise N; Klein, Rachel Herndon; Salmans, Michael L; Gordon, William; Ho, Hsiang; Andersen, Bogi

    2013-11-29

    The cornea is the clear, outermost portion of the eye composed of three layers: an epithelium that provides a protective barrier while allowing transmission of light into the eye, a collagen-rich stroma, and an endothelium monolayer. How cornea development and aging is controlled is poorly understood. Here we characterize the mouse cornea transcriptome from early embryogenesis through aging and compare it with transcriptomes of other epithelial tissues, identifying cornea-enriched genes, pathways, and transcriptional regulators. Additionally, we profiled cornea epithelium and stroma, defining genes enriched in these layers. Over 10,000 genes are differentially regulated in the mouse cornea across the time course, showing dynamic expression during development and modest expression changes in fewer genes during aging. A striking transition time point for gene expression between postnatal days 14 and 28 corresponds with completion of cornea development at the transcriptional level. Clustering classifies co-expressed, and potentially co-regulated, genes into biologically informative categories, including groups that exhibit epithelial or stromal enriched expression. Based on these findings, and through loss of function studies and ChIP-seq, we show that the Ets transcription factor EHF promotes cornea epithelial fate through complementary gene activating and repressing activities. Furthermore, we identify potential interactions between EHF, KLF4, and KLF5 in promoting cornea epithelial differentiation. These data provide insights into the mechanisms underlying epithelial development and aging, identifying EHF as a regulator of cornea epithelial identity and pointing to interactions between Ets and KLF factors in promoting epithelial fate. Furthermore, this comprehensive gene expression data set for the cornea is a powerful tool for discovery of novel cornea regulators and pathways.

  1. Expression of glutathione transferases in corneal cell lines, corneal tissues and a human cornea construct.

    Science.gov (United States)

    Kölln, Christian; Reichl, Stephan

    2016-06-15

    Glutathione transferase (GST) expression and activity were examined in a three-dimensional human cornea construct and were compared to those of excised animal corneas. The objective of this study was to characterize phase II enzyme expression in the cornea construct with respect to its utility as an alternative to animal cornea models. The expression of the GSTO1-1 and GSTP1-1 enzymes was investigated using immunofluorescence staining and western blotting. The level of total glutathione transferase activity was determined using 1-chloro-2,4- dinitrobenzene as the substrate. Furthermore, the levels of GSTO1-1 and GSTP1-1 activity were examined using S-(4-nitrophenacyl)glutathione and ethacrynic acid, respectively, as the specific substrates. The expression and activity levels of these enzymes were examined in the epithelium, stroma and endothelium, the three main cellular layers of the cornea. In summary, the investigated enzymes were detected at both the protein and functional levels in the cornea construct and the excised animal corneas. However, the enzymatic activity levels of the human cornea construct were lower than those of the animal corneas.

  2. Delivery of antisense oligonucleotide to the cornea by iontophoresis.

    Science.gov (United States)

    Berdugo, M; Valamanesh, F; Andrieu, C; Klein, C; Benezra, D; Courtois, Y; Behar-Cohen, F

    2003-04-01

    We wished to evaluate the potential of iontophoresis to promote the delivery of antisense oligonucleotides (ODN) directed at the vascular endothelial growth factor (VEGF)-R2 receptor (KDR/Flk) to the cornea of the rat eye. Fluorescence (CY5)-labeled ODNs in phosphate-buffered saline (PBS) (20 microM) were locally administered to rat eyes, and their fate within the anterior segment was studied. Thirty-four male, 5-week-old Wistar rats were used for all experiments. The rats were divided in four groups. In group I (12 rats, 12 eyes), the ODNs (20 microM) were delivered by iontophoresis (300 microA for 5 minutes) using a specially designed corneal applicator. In group II (12 rats, 12 eyes), the ODNs (20 microM) were delivered using the same applicator, but no electrical current was applied. In group III (6 rats, 6 eyes), a corneal neovascular reaction was induced prior to the application of ODNs (20 microM), and iontophoresis electrical current was delivered as for group I rats. Group IV (4 rats, 4 eyes) received ODN (60 microM) iontophoresis application (300 microA for 5 minutes) and were used for ODN integrity studies. The animals were killed 5 minutes, 90 minutes, and 24 hours after a single ODN application and studied. Topically applied ODNs using the same iontophoresis applicator but without current do not penetrate the cornea and remain confined to the superficial epithelial layer. ODNs delivered with transcorneoscleral iontophoresis penetrate into all corneal layers and are also detected in the iris. In corneas with neovascularization, ODNs were particularly localized within the vascular endothelial cells of the stroma. ODNs extracted from eye tissues 24 hours after iontophoresis remained unaltered. The iontophoresis current did not cause any detectable ocular damage under these conditions. Iontophoresis promotes the delivery of ODNs to the anterior segment of the eye, including all corneal layers. Iontophoresis of ODNs directed at VEGF-R2 may be used for the

  3. An adaptive algorithm for the cornea modeling from keratometric data

    CERN Document Server

    Martinez-Finkelshtein, Andrei; Castro-Luna, Gracia M; Alio, Jorge L

    2010-01-01

    In this paper we describe an adaptive and multi-scale algorithm for the parsimonious fit of the corneal surface data that allows to adapt the number of functions used in the reconstruction to the conditions of each cornea. The method implements also a dynamical selection of the parameters and the management of noise. It can be used for the real-time reconstruction of both altimetric data and corneal power maps from the data collected by keratoscopes, such as the Placido rings based topographers, decisive for an early detection of corneal diseases such as keratoconus. Numerical experiments show that the algorithm exhibits a steady exponential error decay, independently of the level of aberration of the cornea. The complexity of each anisotropic gaussian basis functions in the functional representation is the same, but their parameters vary to fit the current scale. This scale is determined only by the residual errors and not by the number of the iteration. Finally, the position and clustering of their centers,...

  4. Wide-angle cornea-sclera (OCULAR) topography

    Science.gov (United States)

    Klein, Stanley A.; Corzine, John; Corbin, Jacob A.; Wechsler, Sheldon; Carney, Thom

    2002-06-01

    Most corneal topographers are slope-based instruments, measuring corneal slope based on light reflected by the cornea acting as a mirror. This mirror method limits corneal coverage to about 9 mm diameter. Both refractive surgery and contact lens fitting actually require a larger coverage than is obtainable using slope-based instruments. Height-based instruments should be able to measure a cornea/sclera area that is twice the size (four times the area) of slope-based topographers with an accuracy of a few microns. We have been testing a prototype of a new model height-based topographer manufactured by Euclid Systems. We find that single shots can produce a corneal coverage of up to 16 mm vertical and 20 mm horizontal. The heights and slopes in the corneal region have good replicability. Although the scleral region is noisier, it is the only topographer available able to measure scleral topography that is critically important to contact lens fitting. There are a number of improvements to the Euclid software and hardware that would enable it to fill an important niche in eye care and eye research.

  5. Efficient numerical modeling of the cornea, and applications

    Science.gov (United States)

    Gonzalez, L.; Navarro, Rafael M.; Hdez-Matamoros, J. L.

    2004-10-01

    Corneal topography has shown to be an essential tool in the ophthalmology clinic both in diagnosis and custom treatments (refractive surgery, keratoplastia), having also a strong potential in optometry. The post processing and analysis of corneal elevation, or local curvature data, is a necessary step to refine the data and also to extract relevant information for the clinician. In this context a parametric cornea model is proposed consisting of a surface described mathematically by two terms: one general ellipsoid corresponding to a regular base surface, expressed by a general quadric term located at an arbitrary position and free orientation in 3D space and a second term, described by a Zernike polynomial expansion, which accounts for irregularities and departures from the basic geometry. The model has been validated obtaining better adjustment of experimental data than other previous models. Among other potential applications, here we present the determination of the optical axis of the cornea by transforming the general quadric to its canonical form. This has permitted us to perform 3D registration of corneal topographical maps to improve the signal-to-noise ratio. Other basic and clinical applications are also explored.

  6. Morphology, topography, and optics of the orthokeratology cornea

    Science.gov (United States)

    Faria-Ribeiro, Miguel; Belsue, Rafael Navarro; López-Gil, Norberto; González-Méijome, José Manuel

    2016-07-01

    The goal of this work was to objectively characterize the external morphology, topography, and optics of the cornea after orthokeratology (ortho-k). A number of 24 patients between the ages of 17 and 30 years (median=24 years) were fitted with Corneal Refractive Therapy® contact lenses to correct myopia between -2.00 and -5.00 diopters (D) (median=-3.41 D). A classification algorithm was applied to conduct an automatic segmentation based on the mean local curvature. As a result, three zones (optical zone, transition zone, and peripheral zone) were delimited. Topographical analysis was provided through global and zonal fit to a general ellipsoid. Ray trace on partially customized eye models provided wave aberrations and retinal image quality. Monozone topographic description of the ortho-k cornea loses accuracy when compared with zonal description. Primary (C40) and secondary (C60) spherical aberration (SA) coefficients for a 5-mm pupil increased 3.68 and 19 times, respectively, after the treatments. The OZ area showed a strong correlation with C40 (r=-0.49, p<0.05) and a very strong correlation with C60 (r=0.78, p<0.01). The OZ, as well as the TZ, areas did not correlate with baseline refraction. The increase in the eye's positive SA after ortho-k is the major factor responsible for the decreased retinal optical quality of the unaccommodated eye.

  7. Molecular cloning of a new angiopoietinlike factor from the human cornea

    NARCIS (Netherlands)

    Peek, R; van Gelderen, BE; Bruinenberg, M; Kijlstra, A

    PURPOSE. To isolate tissue-specific gene products that contribute to corneal integrity. METHODS. A cDNA library was constructed and differentially hybridized. Cornea-specific clones were purified and further characterized. RESULTS. In this study cornea-specific gene products were isolated by

  8. Multiphoton Imaging of Rabbit Cornea Treated with Mitomycin C after Photorefractive Keratectomy

    Science.gov (United States)

    Hsueh, Chiu-Mei; Lo, Wen; Wang, Tsung-Jen; Hu, Fung-Rong; Dong, Chen-Yuan

    2007-07-01

    In this work we use multiphoton microscopy to observe the post surgery structure variation of rabbit cornea after photorefractive keratectomy (PRK). In addition, we added mitomycin C (MMC) to the post surgery rabbit cornea in order to investigate the effect of MMC treatment on the postoperative regeneration.

  9. 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....

  10. 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.

  11. Prevalence and clinical consequences of herpes simplex virus type 1 DNA in human cornea tissues

    NARCIS (Netherlands)

    L. Remeijer (Lies); R. Duan (Rui); J.M. van Dun (Jessica); M.A.W. Bettink; A.D.M.E. Osterhaus (Albert); G.M.G.M. Verjans (George)

    2009-01-01

    textabstractBackground. We determined the prevalence and clinical consequences of herpes simplex virus (HSV) type 1 (HSV-1), HSV type 2 (HSV-2), and varicella-zoster virus (VZV) in cornea tissues obtained after penetrating keratoplasty (PKP) was performed. Methods. The excised corneas of 83 patients

  12. Prevalence and clinical consequences of herpes simplex virus type 1 DNA in human cornea tissues

    NARCIS (Netherlands)

    L. Remeijer (Lies); R. Duan (Rui); J.M. van Dun (Jessica); M.A.W. Bettink; A.D.M.E. Osterhaus (Ab); G.M.G.M. Verjans (George)

    2009-01-01

    textabstractBackground. We determined the prevalence and clinical consequences of herpes simplex virus (HSV) type 1 (HSV-1), HSV type 2 (HSV-2), and varicella-zoster virus (VZV) in cornea tissues obtained after penetrating keratoplasty (PKP) was performed. Methods. The excised corneas of 83 patients

  13. Enrichment of pathogenic alleles in the brittle cornea gene, ZNF469, in keratoconus

    Science.gov (United States)

    Lechner, Judith; Porter, Louise F.; Rice, Aine; Vitart, Veronique; Armstrong, David J.; Schorderet, Daniel F.; Munier, Francis L.; Wright, Alan F.; Inglehearn, Chris F.; Black, Graeme C.; Simpson, David A.; Manson, Forbes; Willoughby, Colin E.

    2014-01-01

    Keratoconus, a common inherited ocular disorder resulting in progressive corneal thinning, is the leading indication for corneal transplantation in the developed world. Genome-wide association studies have identified common SNPs 100 kb upstream of ZNF469 strongly associated with corneal thickness. Homozygous mutations in ZNF469 and PR domain-containing protein 5 (PRDM5) genes result in brittle cornea syndrome (BCS) Types 1 and 2, respectively. BCS is an autosomal recessive generalized connective tissue disorder associated with extreme corneal thinning and a high risk of corneal rupture. Some individuals with heterozygous PRDM5 mutations demonstrate a carrier ocular phenotype, which includes a mildly reduced corneal thickness, keratoconus and blue sclera. We hypothesized that heterozygous variants in PRDM5 and ZNF469 predispose to the development of isolated keratoconus. We found a significant enrichment of potentially pathologic heterozygous alleles in ZNF469 associated with the development of keratoconus (P = 0.00102) resulting in a relative risk of 12.0. This enrichment of rare potentially pathogenic alleles in ZNF469 in 12.5% of keratoconus patients represents a significant mutational load and highlights ZNF469 as the most significant genetic factor responsible for keratoconus identified to date. PMID:24895405

  14. Enrichment of pathogenic alleles in the brittle cornea gene, ZNF469, in keratoconus.

    Science.gov (United States)

    Lechner, Judith; Porter, Louise F; Rice, Aine; Vitart, Veronique; Armstrong, David J; Schorderet, Daniel F; Munier, Francis L; Wright, Alan F; Inglehearn, Chris F; Black, Graeme C; Simpson, David A; Manson, Forbes; Willoughby, Colin E

    2014-10-15

    Keratoconus, a common inherited ocular disorder resulting in progressive corneal thinning, is the leading indication for corneal transplantation in the developed world. Genome-wide association studies have identified common SNPs 100 kb upstream of ZNF469 strongly associated with corneal thickness. Homozygous mutations in ZNF469 and PR domain-containing protein 5 (PRDM5) genes result in brittle cornea syndrome (BCS) Types 1 and 2, respectively. BCS is an autosomal recessive generalized connective tissue disorder associated with extreme corneal thinning and a high risk of corneal rupture. Some individuals with heterozygous PRDM5 mutations demonstrate a carrier ocular phenotype, which includes a mildly reduced corneal thickness, keratoconus and blue sclera. We hypothesized that heterozygous variants in PRDM5 and ZNF469 predispose to the development of isolated keratoconus. We found a significant enrichment of potentially pathologic heterozygous alleles in ZNF469 associated with the development of keratoconus (P = 0.00102) resulting in a relative risk of 12.0. This enrichment of rare potentially pathogenic alleles in ZNF469 in 12.5% of keratoconus patients represents a significant mutational load and highlights ZNF469 as the most significant genetic factor responsible for keratoconus identified to date.

  15. 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

    2015-01-22

    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.

  16. Tissue Engineering the Cornea: The Evolution of RAFT

    Directory of Open Access Journals (Sweden)

    Hannah J. Levis

    2015-01-01

    Full Text Available 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.

  17. Epithelial ion transport in rabbit corneas following myopic keratomileusis.

    Science.gov (United States)

    Swinger, C A; Candia, O A; Marcus, S; Barker, B A; Kornmehl, E W

    1986-08-01

    In isolated rabbit corneas that had undergone lamellar keratectomy or myopic keratomileusis, the stimulation of chloride transport by 10(-5) M epinephrine was completely inhibited at 1 week following surgery. At 28 days following surgery, both groups responded to 10(-7) M epinephrine. The response to 10(-5) M amphotericin B was normal both at 1 week and at 28 days following surgery. We conclude that, although the Na-K pump was not affected by the lamellar keratectomy and cryolathing, that either the epithelial beta receptors and/or the cAMP pathway were temporarily inhibited for at least 1 week following surgery. A lamellar keratectomy, therefore, can have an adverse effect on the epithelial transport system of the corneal epithelium even though the epithelium may appear normal clinically.

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

    Science.gov (United States)

    Sızmaz, Selçuk; Bingöllü, Sibel; Erdem, Elif; Kibar, Filiz; Koltaş, Soner; Yağmur, Meltem; Ersöz, Reha

    2016-01-01

    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. PMID:27800266

  19. 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

  20. 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.

  1. Reconstruction of damaged cornea by autologous transplantation of epidermal adult stem cells.

    Science.gov (United States)

    Yang, Xueyi; Moldovan, Nicanor I; Zhao, Qingmei; Mi, Shengli; Zhou, Zhenhui; Chen, Dan; Gao, Zhimin; Tong, Dewen; Dou, Zhongying

    2008-06-05

    It is crucial for the treatment of severe ocular surface diseases such as Stevens-Johnson syndrome (SJS) and ocular cicatricial pemphigoid (OCP) to find strategies that avoid the risks of allograft rejection and immunosuppression. Here, we report a new strategy for reconstructing the damaged corneal surface in a goat model of total limbal stem cell deficiency (LSCD) by autologous transplantation of epidermal adult stem cells (EpiASC). EpiASC derived from adult goat ear skin by explant culture were purified by selecting single cell-derived clones. These EpiASC were cultivated on denuded human amniotic membrane (HAM) and transplanted onto goat eyes with total LSCD. The characteristics of both EpiASC and reconstructed corneal epithelium were identified by histology and immunohistochemistry. The clinical characteristic of reconstructed corneal surface was observed by digital camera. Ten LSCD goats (10 eyes) were treated with EpiASC transplantation, leading to the restoration of corneal transparency and improvement of postoperative visual acuity to varying degrees in 80.00% (8/10) of the experimental eyes. The corneal epithelium of control groups either with HAM transplantation only or without any transplantation showed irregular surfaces, diffuse vascularization, and pannus on the entire cornea. The reconstructed corneal epithelium (RCE) expressed CK3, CK12, and PAX-6 and had the function of secreting glycocalyx-like material (AB-PAS positive). During the follow-up period, all corneal surfaces remained transparent and there were no serious complications. We also observed that the REC expressed CK1/10 weakly at six months after operation but not at 12 months after operation, suggesting that the REC was derived from grafted EpiASC. Our results showed that EpiASC repaired the damaged cornea of goats with total LSCD and demonstrated that EpiASC can be induced to differentiate into corneal epithelial cell types in vivo, which at least in part correlated with down

  2. Effects of the holmium laser on the human cornea: a preliminary study

    Science.gov (United States)

    Mueller, Linda J.; Tassignon, Marie J.; Trau, Rene; Pels, Liesbeth; Vrensen, Gijs F.

    1996-12-01

    Treatment of peripheral post-mortem human corneas with the Holmium laser in a ring pattern resulted in opaque spots. One pair of treated eyes was immediately processed for light and electron microscopy and three other treated eyes were preserved for 4 days in medium in order to compare direct and short-term effects of the Holmium laser. Cross as well as frontal light microscopical sections of all eyes revealed interconnecting bands between the spots. At the ultrastructural level the anterior corneal tissue within these spots was characterized by coagulation of cells and collagen and shoed either a dramatic distorting effect on the epithelium in the eyes processed immediately or a single layer of flattened multi-nucleolated epithelial cells having more than one nucleolus per nucleus in the eyes stored in medium. Furthermore, the spots showed disturbed Bowman's layer, destroyed keratocytes and collagen fibrils which were either coagulated or organized chaotically. The interconnecting bands contained alternating normal and coagulated collagen fibers. The rest of the cornea outside the spots had a normal appearance. In corneas stored in medium, both keratocytes and epithelial cells over the entire cornea exhibited accumulations of cytoplasmic fibrils and glycogen particles. These phenomena were not observed in non-preserved corneas, suggesting that the differences are due to preservation and not due to the laser treatment. It is concluded that morphological changes occur mainly in the treated peripheral cornea whereas the central untreated cornea remains unaffected,indicating that the Holmium laser is a reliable instrument to treat hypermetropic patients.

  3. Preliminary study on the effect of stiffness on lamb wave propagation in bovine corneas.

    Science.gov (United States)

    Zhang, Xin-Yu; Yin, Yin; Guo, Yan-Rong; Diao, Xian-Fen; Chen, Xin

    2013-01-01

    The viscoelastic properties of human cornea could provide valuable information for various clinical applications. Particularly, it will be helpful to achieve a patient-specific biomechanical optimization in LASIK refractive surgery, early detection of corneal ecstatic disease or improved accuracy of intraocular pressure (IOP) measurement. However, there are few techniques that are capable of accurately assessing the corneal elasticity in situ in a nondestructive fashion. In order to develop a quantitative method for assessing both elasticity and viscosity of the cornea, we use ultrasound radiation force to excite Lamb waves in cornea, and a pulse echo transducer to track the tissue vibration. The fresh postmortem bovine eyes were treated via collagen cross-linking to make the cornea stiff. The effect of stiffness was studied by comparing the propagation of Lamb waves in normal and treated corneas. It was found that the waveform of generated Lamb waves changed significantly due to the increase in higher modes in treated corneas. This result indicated that the generated waveform was a complex of multiple harmonics and the varied stiffness will affect the energy distribution over different components. Therefore, it is important for assessing the viscoelastic properties of the cornea to know the components of Lamb wave and calculate the phase velocity appropriately.

  4. Development and characterization of a full-thickness acellular porcine cornea matrix for tissue engineering.

    Science.gov (United States)

    Du, Liqun; Wu, Xinyi

    2011-07-01

    Our aim was to produce a natural, acellular matrix from porcine cornea for use as a scaffold in developing a tissue-engineered cornea replacement. Full-thickness, intact porcine corneas were decellularized by immersion in 0.5% (wt/vol) sodium dodecyl sulfate. The resulting acellular matrices were then characterized and examined specifically for completeness of the decellularization process. Histological analyses of decellularized corneal stromas showed that complete cell and α-Gal removal was achieved, while the major structural proteins including collagen type I and IV, laminin, and fibronectin were retained. DAPI staining did not detect any residual DNA within the matrix, and the DNA contents, which reflect the presence of cellular materials, were significantly diminished in the decellularized cornea. The collagen content of the decellularized cornea was well maintained compared with native tissues. Uniaxial tensile testing indicated that decellularization did not significantly compromise the ultimate tensile strength of the tissue (P > 0.05). In vitro cytotoxicity assays using rabbit corneal fibroblast cultures excluded the presence of soluble toxins in the biomaterial. In vivo implantation to rabbit interlamellar stromal pockets showed good biocompability. In summary, a full-thickness natural acellular matrix retaining the major structural components and strength of the cornea has been successfully developed. The matrix is biocompatible with cornea-derived cells and has potential for use in corneal transplantation and tissue-engineering applications. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  5. Cornea donors who have had prior refractive surgery: data from the Eye Bank Association of America.

    Science.gov (United States)

    Fargione, Robert A; Channa, Prabjot

    2016-07-01

    Millions of Americans have undergone refractive surgeries, including radial keratotomy, photorefractive keratectomy, and laser-assisted in situ keratomileusis. Eye Bank Association of America medical standards do not permit corneas from patients who have undergone refractive procedures to be used in penetrating keratoplasty, anterior lamellar keratoplasty, or tectonic grafting procedures. Such corneas, can, however, be used for endothelial corneal transplantation. The objective of this article is to provide an update on current trends for the screening and usage of corneas that have undergone refractive surgery. Several case reports have highlighted the difficulty in using postrefractive surgery corneas in penetrating keratoplasty. However, tissue with anterior stromal flaws, including a history of refractive surgery, has been used in endothelial keratoplasty with equivalent outcomes in topography, endothelial cell count, and visual acuity. Many modalities for proper identification of postmortem donor corneas that have undergone refractive surgery have been studied. Corneas with a history of refractive surgery have found use in endothelial keratoplasty. Multiple objective methods of tissue identification have been investigated to avoid the use of these corneas in penetrating or anterior keratoplasty surgeries.

  6. Imaging of Keratoconic and normal human cornea with a Brillouin imaging system (Conference Presentation)

    Science.gov (United States)

    Besner, Sebastien; Shao, Peng; Scarcelli, Giuliano; Pineda, Roberto; Yun, Seok-Hyun (Andy)

    2016-03-01

    Keratoconus is a degenerative disorder of the eye characterized by human cornea thinning and morphological change to a more conical shape. Current diagnosis of this disease relies on topographic imaging of the cornea. Early and differential diagnosis is difficult. In keratoconus, mechanical properties are found to be compromised. A clinically available invasive technique capable of measuring the mechanical properties of the cornea is of significant importance for understanding the mechanism of keratoconus development and improve detection and intervention in keratoconus. The capability of Brillouin imaging to detect local longitudinal modulus in human cornea has been demonstrated previously. We report our non-contact, non-invasive, clinically viable Brillouin imaging system engineered to evaluate mechanical properties human cornea in vivo. The system takes advantage of a highly dispersive 2-stage virtually imaged phased array (VIPA) to detect weak Brillouin scattering signal from biological samples. With a 1.5-mW light beam from a 780-nm single-wavelength laser source, the system is able to detect Brillouin frequency shift of a single point in human cornea less than 0.3 second, at a 5μm/30μm lateral/axial resolution. Sensitivity of the system was quantified to be ~ 10 MHz. A-scans at different sample locations on a human cornea with a motorized human interface. We imaged both normal and keratoconic human corneas with this system. Whereas no significantly difference were observed outside keratocnic cones compared with normal cornea, a highly statistically significantly decrease was found in the cone regions.

  7. A comparison of three methods of decellularization of pig corneas to reduce immunogenicity

    Institute of Scientific and Technical Information of China (English)

    Whayoung; Lee; Yuko; Miyagawa; Cassandra; Long; David; K.; C.; Cooper; Hidetaka; Hara

    2014-01-01

    ·AIM: To investigate whether decellularization using different techniques can reduce immunogenicity of the cornea, and to explore the decellularized cornea as a scaffold for cultured corneal endothelial cells(CECs).Transplantation of decellularized porcine corneas increases graft transparency and survival for longer periods compared with fresh grafts.·METHODS: Six-month-old wild-type pig corneas were cut into 100-200 μm thickness, and then decellularized by three different methods: 1) 0.1% sodium dodecyl sulfate(SDS); 2) hypoxic nitrogen(N2); and 3) hypertonic NaCl. Thickness and transparency were assessed visually. Fresh and decellularized corneas were stained with hematoxylin/eosin(H&E), and for the presence of galactose-α1,3-galactose(Gal) and N-glycolylneuraminic acid(NeuGc, a nonGal antigen). Also, a human IgM/IgG binding assay was performed. Cultured porcine CECs were seeded on the surface of the decellularized cornea and examined after H&E staining.· RESULTS: All three methods of decellularization reduced the number of keratocytes in the stromal tissue by >80% while the collagen structure remained preserved. No remaining nuclei stained positive for Gal or NeuGc, and expression of these oligosaccharides on collagen was also greatly decreased compared to expression on fresh corneas. Human IgM/IgG binding to decellularized corneal tissue was considerably reduced compared to fresh corneal tissue. The cultured CECs formed a confluent monolayer on the surface of decellularized tissue.· CONCLUSION: Though incomplete, the significant reduction in the cellular component of the decellularized cornea should be associated with a significantly reduced in vivo immune response compared to fresh corneas.

  8. 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

  9. An Immunohistochemical Study of Langerhans Cells,T-Cells and the HLA Antigen in Human Cornea

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    The distribution of Langerhans cells (LC),T-cell subsets andHLA antigen in 12 normal and 7 morbid corneas,including 4 of suppurativecorneal ulcer and 3 of uveogenic endophthalmitis,was investigated withmonoclonal antibodies.The results revealed that a small amount of LC andT-cell subsets were present in the limbal region of normal corneas,whilelarge numbers of LC and OKT_4~+ were observed in the corneas of suppurativeulcer.HLA-A,B,C antigens were expressed on the epithelial cells andkeratocytes of the n...

  10. Dual-path handheld system for cornea and retina imaging using optical coherence tomography

    Science.gov (United States)

    Shirazi, Muhammad Faizan; Wijesinghe, Ruchire Eranga; Ravichandran, Naresh Kumar; Kim, Pilun; Jeon, Mansik; Kim, Jeehyun

    2016-11-01

    A dual-path handheld system is proposed for cornea and retina imaging using spectral domain optical coherence tomography. The handheld sample arm is designed to acquire two images simultaneously. Both eyes of a person can be imaged at the same time to obtain the images of the cornea of one eye and the retina of the other eye. Cornea, retina, and optic disc images are acquired with the proposed sample arm. Experimental results demonstrate the usefulness of this system for imaging of different eye segments. This system reduces the time required for imaging of the two eyes and is cost effective.

  11. A time-delay calibrated method for cornea hysteresis and intraocular pressure measurement

    Science.gov (United States)

    Wang, Kuo-Jen; Tsai, Che-Liang; Wang, Wai; Hsu, Long; Hsu, Ken-Yuh

    2016-04-01

    The presence of cornea hysteresis (CH) in characterizing the intraocular pressure (IOP) of a human eye deteriorates the accuracy of IOP. To suppress CH, the pressure gauge of a tonometer must be located as close as possible to the cornea. However, this arrangement is unpractical because appropriate working distance to the cornea is required. In this paper, a time-delay calibrated (TDC) method is proposed to counteract the undesired effect of CH in characterizing the IOP. Employing this TDC method, the CH approaches to zero for most eyes measured.

  12. Coherent states and geodesics cut locus and conjugate locus

    CERN Document Server

    Berceanu, S

    1997-01-01

    The intimate relationship between coherent states and geodesics is pointed out. For homogenous manifolds on which the exponential from the Lie algebra to the Lie group equals the geodesic exponential, and in particular for symmetric spaces, it is proved that the cut locus of the point $0$ is equal to the set of coherent vectors orthogonal to $\\vert 0>$. A simple method to calculate the conjugate locus in Hermitian symmetric spaces with significance in the coherent state approach is presented. The results are illustrated on the complex Grassmann manifold.

  13. An unusual case of nephrotic syndrome

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    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.

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

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    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

  15. [Study on preferred retinal locus].

    Science.gov (United States)

    Dai, Bing-Fa; Hu, Jian-Min; Xu, Duan-Lian

    2012-03-01

    Preferred retinal locus (PRL) is always found in the age-related macular degeneration and other macular damages in patients with low vision, and it is a very important anatomic position in patients with central vision impairment to achieve the rehabilitation. In recent years, the training of preferred retinal locus (PRL) has become a research hotspot of low vision rehabilitation, it can clearly improve functional vision and quality of life. The authors reviewed relevant literatures, and summarized the definition, position, characteristics, training and clinical implications of the PRL.

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

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    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

  17. Zinc oxide tetrapods inhibit herpes simplex virus infection of cultured corneas

    Science.gov (United States)

    Duggal, Neil; Jaishankar, Dinesh; Yadavalli, Tejabhiram; Hadigal, Satvik; Mishra, Yogendra Kumar; Adelung, Rainer

    2017-01-01

    Purpose Infection of the human cornea by herpes simplex virus type-1 (HSV-1) can cause significant vision loss. The purpose of this study was to develop an ex vivo model to visualize viral growth and spread in the cornea. The model was also used to analyze cytokine production and study the antiviral effects of zinc oxide tetrapods. Methods A β-galactosidase-expressing recombinant virus, HSV-1(KOS)tk12, was used to demonstrate the ability of the virus to enter and develop blue plaques on human corneal epithelial (HCE) cells and corneal tissues. Freshly obtained porcine corneas were cultured and then scratched before infection with HSV-1(KOS)tk12. The blue plaques on the corneas were imaged using a stereomicroscope. Western blot analysis for HSV-1 proteins was performed to verify HSV-1 infection of the cornea. Using the ex vivo model, zinc oxide tetrapods were tested for their anti-HSV-1 potential, and a cytokine profile was developed to assess the effects of the treatment. Results Cultured corneas and the use of β-galactosidase-expressing HSV-1(KOS)tk12 virus can provide an attractive ex vivo model to visualize and study HSV-1 entry and spread of the infection in tissues. We found that unlike cultured HCE cells, which demonstrated nearly 100% infectivity, HSV-1 infection of the cultured cornea was more restrictive and took longer to develop. We also found that the zinc oxide tetrapod–shaped nano- and microstructures inhibited HSV infection of the cultured cells, as well as the cultured corneas. The cytokine profile of the infected samples was consistent with previous studies of HSV-1 corneal infection. Conclusions The ability to visualize HSV-1 growth and spread in corneal tissues can provide new details about HSV-1 infection of the cornea and the efficacy of new cornea-specific antiviral drug candidates. The ex vivo model also demonstrates antiviral effects of zinc oxide tetrapods and adequately portrays the drug delivery issues that cornea-specific treatments

  18. Diabetic cornea wounds produce significantly weaker electric signals that may contribute to impaired healing

    OpenAIRE

    Yunyun Shen; Trisha Pfluger; Fernando Ferreira; Jiebing Liang; Navedo, Manuel F; Qunli Zeng; Brian Reid; Min Zhao

    2016-01-01

    Wounds naturally produce electric signals which serve as powerful cues that stimulate and guide cell migration during wound healing. In diabetic patients, impaired wound healing is one of the most challenging complications in diabetes management. A fundamental gap in knowledge is whether diabetic wounds have abnormal electric signaling. Here we used a vibrating probe to demonstrate that diabetic corneas produced significantly weaker wound electric signals than the normal cornea. This was conf...

  19. Hyperglycemia-induced abnormalities in rat and human corneas: the potential of second harmonic generation microscopy.

    Directory of Open Access Journals (Sweden)

    Gaël Latour

    Full Text Available BACKGROUND: Second Harmonic Generation (SHG microscopy recently appeared as an efficient optical imaging technique to probe unstained collagen-rich tissues like cornea. Moreover, corneal remodeling occurs in many diseases and precise characterization requires overcoming the limitations of conventional techniques. In this work, we focus on diabetes, which affects hundreds of million people worldwide and most often leads to diabetic retinopathy, with no early diagnostic tool. This study then aims to establish the potential of SHG microscopy for in situ detection and characterization of hyperglycemia-induced abnormalities in the Descemet's membrane, in the posterior cornea. METHODOLOGY/PRINCIPAL FINDINGS: We studied corneas from age-matched control and Goto-Kakizaki rats, a spontaneous model of type 2 diabetes, and corneas from human donors with type 2 diabetes and without any diabetes. SHG imaging was compared to confocal microscopy, to histology characterization using conventional staining and transmitted light microscopy and to transmission electron microscopy. SHG imaging revealed collagen deposits in the Descemet's membrane of unstained corneas in a unique way compared to these gold standard techniques in ophthalmology. It provided background-free images of the three-dimensional interwoven distribution of the collagen deposits, with improved contrast compared to confocal microscopy. It also provided structural capability in intact corneas because of its high specificity to fibrillar collagen, with substantially larger field of view than transmission electron microscopy. Moreover, in vivo SHG imaging was demonstrated in Goto-Kakizaki rats. CONCLUSIONS/SIGNIFICANCE: Our study shows unambiguously the high potential of SHG microscopy for three-dimensional characterization of structural abnormalities in unstained corneas. Furthermore, our demonstration of in vivo SHG imaging opens the way to long-term dynamical studies. This method should be easily

  20. Material Properties from Air Puff Corneal Deformation by Numerical Simulations on Model Corneas

    Science.gov (United States)

    Dorronsoro, Carlos; de la Hoz, Andrés; Marcos, Susana

    2016-01-01

    Objective To validate a new method for reconstructing corneal biomechanical properties from air puff corneal deformation images using hydrogel polymer model corneas and porcine corneas. Methods Air puff deformation imaging was performed on model eyes with artificial corneas made out of three different hydrogel materials with three different thicknesses and on porcine eyes, at constant intraocular pressure of 15 mmHg. The cornea air puff deformation was modeled using finite elements, and hyperelastic material parameters were determined through inverse modeling, minimizing the difference between the simulated and the measured central deformation amplitude and central-peripheral deformation ratio parameters. Uniaxial tensile tests were performed on the model cornea materials as well as on corneal strips, and the results were compared to stress-strain simulations assuming the reconstructed material parameters. Results The measured and simulated spatial and temporal profiles of the air puff deformation tests were in good agreement (< 7% average discrepancy). The simulated stress-strain curves of the studied hydrogel corneal materials fitted well the experimental stress-strain curves from uniaxial extensiometry, particularly in the 0–0.4 range. Equivalent Young´s moduli of the reconstructed material properties from air-puff were 0.31, 0.58 and 0.48 MPa for the three polymer materials respectively which differed < 1% from those obtained from extensiometry. The simulations of the same material but different thickness resulted in similar reconstructed material properties. The air-puff reconstructed average equivalent Young´s modulus of the porcine corneas was 1.3 MPa, within 18% of that obtained from extensiometry. Conclusions Air puff corneal deformation imaging with inverse finite element modeling can retrieve material properties of model hydrogel polymer corneas and real corneas, which are in good correspondence with those obtained from uniaxial extensiometry

  1. Ocular allergic inflammation: interaction between the cornea and conjunctiva.

    Science.gov (United States)

    Fukuda, Ken; Nishida, Teruo

    2010-11-01

    Severe ocular allergic diseases such as vernal keratoconjunctivitis are characterized not only by conjunctival allergic inflammation, including infiltration of T helper 2 cells and eosinophils into the conjunctiva, but also by various corneal disorders such as persistent epithelial defects and shield ulcer. Although the cornea and conjunctiva are thought to influence each other during ocular allergic inflammation, direct evidence for interaction between these tissues in vivo has been lacking. Eosinophils and eosinophil-derived factors are implicated in the pathogenesis of corneal lesions associated with ocular allergy, with cytotoxic granule proteins such as major basic protein and matrix metalloproteinase 9 derived from eosinophils having been detected in shield ulcer. Major basic protein exhibits cytotoxic effects in cultured corneal epithelial cells and inhibits corneal epithelial wound healing in organ culture, whereas matrix metalloproteinase 9 can degrade the corneal epithelial basement membrane. In vitro studies have revealed that cytokines and other inflammatory mediators directly impair the barrier function of corneal epithelial cells and increase the expression of chemokines and adhesion molecules by corneal stromal fibroblasts, effects that may enhance allergic inflammation. We have recently shown that removal of the corneal epithelium augmented late-phase clinical signs and conjunctival eosinophilia, whereas conjunctival inflammation delayed corneal epithelial wound healing, in a rat model of ocular allergy. Conjunctival allergic inflammation and corneal epithelial disorders thus interact with each other in vivo to generate a vicious cycle, interruption of which might provide the basis for novel approaches to the treatment of severe ocular allergy.

  2. 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.

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

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    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.

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

    Directory of Open Access Journals (Sweden)

    Anne Bukowiecki

    2017-06-01

    Full Text Available 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.

  5. Human cornea wound healing in organ culture after Er:YAG laser ablation

    Science.gov (United States)

    Shen, Jin-Hui; Joos, Karen M.; Robinson, Richard D.; Shetlar, Debra J.; O'Day, Denis M.

    1998-06-01

    Purpose: To study the healing process in cultured human corneas after Er:YAG laser ablation. Methods: Human cadaver corneas within 24 hours post mortem were ablated with a Q- switched Er:YAG laser at 2.94 micrometer wavelength. The radiant exposure was 500 mJ/cm2. The cornea was cultured on a tissue supporting frame immediately after the ablation. Culture media consisted of 92% minimum essential media, 8% fetal bovine serum, 0.125% HEPES buffer solution, 0.125% gentamicin, and 0.05% fungizone. The entire tissue frame and media container were kept in an incubator at 37 degrees Celsius and 5% CO2. Serial macroscopic photographs of the cultured corneas were taken during the healing process. Histology was performed after 30 days of culture. Results: A clear ablated crater into the stroma was observed immediately after the ablation. The thickness of thermal damage ranges between 1 and 25 micrometer. Haze development within the crater varies from the third day to the fourteenth day according to the depth and the roughness of the crater. Histologic sections of the cultured cornea showed complete re- epithelization of the lased area. Loose fibrous tissue is observed filling the ablated space beneath the epithelium. The endothelium appeared unaffected. Conclusions: The intensity and time of haze development appears dependent upon the depth of the ablation. Cultured human corneas may provide useful information regarding the healing process following laser ablation.

  6. 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.

  7. Locus of Control and Interpersonal Attraction.

    Science.gov (United States)

    Fagan, M. Michael

    1980-01-01

    The role of locus of control in interpersonal attraction was examined by administering 1) the Nowicki-Strickland Locus of Control Scale and 2) a sociometric test of friendship to 200 eighth graders. (CM)

  8. Effect of epithelial debridement on human cornea proteoglycans

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    E.S. Soriano

    2001-03-01

    Full Text Available Corneal transparency is attributed to the regular spacing and diameter of collagen fibrils, and proteoglycans may play a role in fibrillogenesis and matrix assembly. Corneal scar tissue is opaque and this opacity is explained by decreased ultrastructural order that may be related to proteoglycan composition. Thus, the objectives of the present study were to characterize the proteoglycans synthesized by human corneal explants and to investigate the effect of mechanical epithelial debridement. Human corneas unsuitable for transplants were immersed in F-12 culture medium and maintained under tissue culture conditions. The proteoglycans synthesized in 24 h were labeled metabolically by the addition of 35S-sulfate to the medium. These compounds were extracted by 4 M GuHCl and identified by a combination of agarose gel electrophoresis, enzymatic degradation with protease and mucopolysaccharidases, and immunoblotting. Decorin was identified as the main dermatan sulfate proteoglycan and keratan sulfate proteoglycans were also prominent components. When the glycosaminoglycan side chains were analyzed, only keratan sulfate and dermatan sulfate were detected (~50% each. Nevertheless, when these compounds were 35S-labeled metabolically, the label in dermatan sulfate was greater than in keratan sulfate, suggesting a lower synthesis rate for keratan sulfate. 35S-Heparan sulfate also appeared. The removal of the epithelial layer caused a decrease in heparan sulfate labeling and induced the synthesis of dermatan sulfate by the stroma. The increased deposit of dermatan sulfate proteoglycans in the stroma suggests a functional relationship between epithelium and stroma that could be related to the corneal opacity that may appear after epithelial cell debridement.

  9. Bevacizumab application delays epithelial healing in rabbit cornea.

    Science.gov (United States)

    Kim, Tae-im; Chung, Jae Lim; Hong, Jin Pyo; Min, Kyung; Seo, Kyoung Yul; Kim, Eung Kweon

    2009-10-01

    Vascular endothelial growth factor (VEGF) is essential for neovascularization, but the use of anti-VEGF therapies to inhibit neovascularization may influence epithelial wound healing. Here, the effects of bevacizumab on corneal epithelial wound healing time in rabbit models, cell proliferation, and expression of integrins in human corneal epithelial and fibroblast cells were evaluated. To compare epithelial wound healing times, epithelial defect sizes were measured after application of bevacizumab topical eye drops at 0, 0.5, 1.0, 1.5, 2.5, or 5 mg/mL, twice daily, to mechanically debrided epithelia of rabbit corneas. The cellular covering of wounded areas and expression of Ki67 were assessed after scrape injuries in cultures of human corneal epithelial and fibroblast cells. Expression of cell surface integrins and collagens was measured using plates coated with mouse monoclonal antibodies against human adhesion molecules, and relevant mRNA levels were assessed by reverse-transcription-polymerase chain reaction (RT-PCR). The application of bevacizumab topical eye drops at 1.0, 1.5, 2.5, or 5 mg/mL delayed rabbit corneal epithelial healing. Cell cultures growing under high concentrations of bevacizumab showed delay in the proliferation of corneal epithelial and fibroblast cells. Surface expression of mRNA encoding integrins and collagens were decreased by 1.5 mg/mL of bevacizumab. Bevacizumab delayed corneal epithelial wound healing and inhibited integrin expression. When bevacizumab is used to reduce the development of new corneal vessels, slight delays in epithelial wound healing are possible and cellular proliferation is to be expected.

  10. Use of glycerol-preserved corneas for corneal transplants

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    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.

  11. Trasplante de córnea Cornea transplant

    Directory of Open Access Journals (Sweden)

    A. Garralda

    2006-08-01

    Full Text Available La queratoplastia o trasplante de córnea es una de las técnicas quirúrgicas más antiguas de la oftalmología cuyas indicaciones son: 1 tectónicas, para preservar la anatomía e integridad corneal, 2 clínicas, para eliminar el tejido corneal inflamado en casos refractarios al tratamiento médico, 3 ópticas, para mejorar la agudeza visual y 4 cosméticas para mejorar el aspecto del ojo. El perfeccionamiento en la técnica y en el instrumental, así como en el tratamiento postoperatorio y en los medios de conservación del tejido donante han mejorado la supervivencia de los injertos realizados. El Modelo Pamplona de coordinación de trasplantes del Hospital Virgen del Camino (HVC está considerado como original y único en España, y en la logística de este programa se incluye el protocolo de detección y extracción de córneas así como el de queratoplastias.The keratoplasty, or corena transplant, is one of the oldest surgical techniques in opthalmology, whose indication are: 1 tectonic, in order to preserve corneal anatomy and integrity; 2 clinical, in order to eliminate the inflamed corneal tissue in cases refractory to medical treatment; 3 optical, in order to improve visual acuity; and 4 cosmetic, in order to improve the appearance of the eye. Improvements in technique and instruments, as well as in post-operative treatment and the means of preserving donated tissue, have improved survival of the grafts. The Pamplona Model of transplant coordination of the Virgen del Camino Hospital is considered to be original and unique in Spain. The logistics of this program include the protocol for detection and extraction of corneas as well as for keratoplasties.

  12. Gene transfer of integration defective anti-HSV-1 meganuclease to human corneas ex vivo.

    Science.gov (United States)

    Elbadawy, H M; Gailledrat, M; Desseaux, C; Salvalaio, G; Di Iorio, E; Ferrari, B; Bertolin, M; Barbaro, V; Parekh, M; Gayon, R; Munegato, D; Franchin, E; Calistri, A; Palù, G; Parolin, C; Ponzin, D; Ferrari, S

    2014-03-01

    Corneal graft rejection is a major problem in chronic herpetic keratitis (HK) patients with latent infection. A new class of antiviral agents targeting latent and active forms of herpes simplex virus type 1 (HSV-1) is importantly required. Meganucleases are sequence-specific homing endonucleases capable of inducing DNA double-strand breaks. A proof-of-concept experiment has shown that tailor-made meganucleases are efficient against HSV-1 in vitro. To take this work a step forward, we hypothesized that the pre-treatment of human corneas in eye banks using meganuclease-encoding vectors will allow HK patients to receive a medicated cornea to resist the recurrence of the infection and the common graft rejection problem. However, this strategy requires efficient gene delivery to human corneal endothelium. Using recombinant adeno-associated virus, serotype 2/1 (rAAV2/1), efficient gene delivery of a reporter gene was demonstrated in human corneas ex vivo. The optimum viral dose was 3.7 × 10(11) VG with an exposure time of 1 day, followed by 6 days incubation in de-swelling medium. In addition, 12 days incubation can result in transgene expression in excess of 70%. Using similar transduction conditions, meganuclease transgene expression was detected in 39.4% of the endothelial cells after 2 weeks in culture. Reduction of the total viral load in the media and the endothelial cells of corneas infected with HSV-1 was shown. Collectively, this work provides information about the optimum conditions to deliver genetic material to the cornea, and demonstrates for the first time the expression of meganuclease in human corneas ex vivo and its antiviral activity. In conclusion, we demonstrate that the treatment of human corneas in eye banks before transplantation is a new approach to address the unmet clinical needs in corneal diseases.

  13. Speaking rate effects on locus equation slope

    Science.gov (United States)

    Berry, Jeff; Weismer, Gary

    2013-01-01

    A locus equation describes a 1st order regression fit to a scatter of vowel steady-state frequency values predicting vowel onset frequency values. Locus equation coefficients are often interpreted as indices of coarticulation. Speaking rate variations with a constant consonant–vowel form are thought to induce changes in the degree of coarticulation. In the current work, the hypothesis that locus slope is a transparent index of coarticulation is examined through the analysis of acoustic samples of large-scale, nearly continuous variations in speaking rate. Following the methodological conventions for locus equation derivation, data pooled across ten vowels yield locus equation slopes that are mostly consistent with the hypothesis that locus equations vary systematically with coarticulation. Comparable analyses between different four-vowel pools reveal variations in the locus slope range and changes in locus slope sensitivity to rate change. Analyses across rate but within vowels are substantially less consistent with the locus hypothesis. Taken together, these findings suggest that the practice of vowel pooling exerts a non-negligible influence on locus outcomes. Results are discussed within the context of articulatory accounts of locus equations and the effects of speaking rate change. PMID:24535890

  14. Diabetic cornea wounds produce significantly weaker electric signals that may contribute to impaired healing.

    Science.gov (United States)

    Shen, Yunyun; Pfluger, Trisha; Ferreira, Fernando; Liang, Jiebing; Navedo, Manuel F; Zeng, Qunli; Reid, Brian; Zhao, Min

    2016-06-10

    Wounds naturally produce electric signals which serve as powerful cues that stimulate and guide cell migration during wound healing. In diabetic patients, impaired wound healing is one of the most challenging complications in diabetes management. A fundamental gap in knowledge is whether diabetic wounds have abnormal electric signaling. Here we used a vibrating probe to demonstrate that diabetic corneas produced significantly weaker wound electric signals than the normal cornea. This was confirmed in three independent animal models of diabetes: db/db, streptozotocin-induced and mice fed a high-fat diet. Spatial measurements illustrated that diabetic cornea wound currents at the wound edge but not wound center were significantly weaker than normal. Time lapse measurements revealed that the electric currents at diabetic corneas lost the normal rising and plateau phases. The abnormal electric signals correlated significantly with impaired wound healing. Immunostaining suggested lower expression of chloride channel 2 and cystic fibrosis transmembrane regulator in diabetic corneal epithelium. Acute high glucose exposure significantly (albeit moderately) reduced electrotaxis of human corneal epithelial cells in vitro, but did not affect the electric currents at cornea wounds. These data suggest that weaker wound electric signals and impaired electrotaxis may contribute to the impaired wound healing in diabetes.

  15. Prevalence and Associations of Steep Cornea/Keratoconus in Greater Beijing. The Beijing Eye Study

    Science.gov (United States)

    Xu, Liang; Wang, Ya Xing; Guo, Yin; You, Qi Sheng; Jonas, Jost B.

    2012-01-01

    Purpose To evaluate the prevalence and associated factors of steep cornea/keratoconus in the adult Chinese population. Methods The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic examination was performed including optical low-coherence reflectometry. Steep cornea/keratoconus were defined as an anterior corneal refractive power exceeding 48 diopters. Results Mean refractive power of the cornea was 43.16±1.45 diopters (range: 36.51 to 48.46 diopters; flattest meridian) and 43.98±1.52 diopters (range: 37.00 to 52.88 diopters; steepest meridian). A steep cornea/keratoconus defined as corneal refractive power of ≥48 diopters and ≥49 diopters was detected in 27 subjects (prevalence rate: 0.9±0.2%) and 6 (0.2± 0.1%) subjects, respectively. Presence of steep cornea/keratoconus was associated with shorter axial length (Pkeratoconus defined as corneal refractive power of 48+ diopters has a prevalence of 0.9±0.2% among Chinese aged 50 years and above. Its prevalence was significantly associated with the ocular parameters of shorter axial length, smaller interpupillary distance, higher cylindrical and myopic refractive error and lower best corrected visual acuity, however, with none of the systemic parameters tested. PMID:22792169

  16. Outcomes of shunt tube coverage with glycerol preserved cornea versus pericardium.

    Science.gov (United States)

    Wigton, Eric; C Swanner, Jason; Joiner, Wade; Feldman, Alex; McGwin, Gerald; Huisingh, Carrie; Curcio, Christine A; Girkin, Christopher A

    2014-01-01

    Pericardium is a biomaterial widely used for covering the outflow tubes of glaucoma drainage devices. Recently, glycerol preserved cornea has been introduced as an alternative that offers durability and improved cosmesis because of its clarity. We retrospectively reviewed 262 patients in the University of Alabama Birmingham Glaucoma Service who underwent shunt procedures using either cornea tissue or pericardium to cover the tube. The primary outcome measure was the number of erosions of the covering material. Nine out of 101 (8.9%) patients in the pericardium covered group experienced an erosion compared with 3 out of 161 (1.9%) in the cornea covered group. A significant difference was reached with P=0.0125. Median follow-up was 440 days for the cornea group and 331 days for the pericardium group. The type of glaucoma (primary open-angle glaucoma vs. secondary glaucoma) was not associated with the risk of erosion (odds ratio, 0.501; 95% confidence interval, 0.204-1.234). The median time to exposure was 252 days in the pericardium group and 440 days in the cornea group (P=0.0017).

  17. Donor cornea preparation in partial big bubble deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Lim L

    2014-02-01

    Full Text Available Li Lim,1 Samuel Wen Yan Lim21Corneal and External Eye Disease Service, Singapore National Eye Centre, 2Yong Loo Lin School of Medicine, National University of Singapore, SingaporeBackground: The purpose of this paper is to describe a technique of donor cornea preparation to ensure good graft-host apposition in incomplete big bubble deep anterior lamellar keratoplasty.Methods: Following a partial-thickness trephination, manual dissection and excision of corneal stroma was performed. Anwar's big-bubble technique involving a deep stromal air injection was then initiated. However, the big bubble could not extend to the trephination edge and the peripheral residual corneal stroma could not be removed. Donor cornea preparation involving trimming of the posterior lip of the corneal button was then performed and good graft-host apposition was obtained without graft over-ride.Results: We performed peripheral donor cornea trimming prior to allograft placement in order to ensure good graft-host apposition. Postoperatively, best-corrected visual acuity in both eyes was 6/7.5.Conclusion: Donor cornea preparation involving trimming of the posterior lip of the corneal button is a useful technique in instances where the big bubble does not extend to the trephination edge and ensures good graft-host apposition.Keywords: deep anterior lamellar keratoplasty, incomplete Anwar big bubble deep anterior lamellar keratoplasty, donor cornea preparation

  18. 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

    2016-01-01

    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. PMID:27006259

  19. Stromal Interleukin-1 Expression in the Cornea after Haze-associated Injury

    Science.gov (United States)

    Barbosa, F. L.; Chaurasia, S.; Kaur, H.; de Medeiros, F. W.; Agrawal, V.; Wilson, S. E.

    2010-01-01

    The purpose of this study was to determine whether myofibroblasts or other cells in the stroma in the cornea produce interleukin (IL)-1α or IL-1β that could modulate myofibroblast viability in corneas with haze after photorefractive keratectomy (PRK). Twenty-four female rabbits had haze-generating PRK for 9 diopters of myopia and were sacrificed at 1 week, 2 weeks, 3 weeks or 4 weeks after surgery. Corneal rims were removed, frozen in OCT at −80°C, and analyzed by immunocytochemistry using primary antibodies to IL-1α, IL-1β and alpha smooth muscle actin (SMA). Double immunostaining was performed for the co-localization of SMA with IL-1α or IL-1β. Central dense haze and peripheral slight haze regions of each cornea were analyzed. SMA+ cells that expressed IL-1α protein were detected in both regions of the corneas at most time points following PRK. However, in the haze region at the 1, 3 and 4 week time points, significantly more (pcorneal fibroblasts, keratocytes, or inflammatory cells may produce IL-1α and/or IL-1β that could act in paracrine fashion to regulate myofibroblast apoptosis—especially in the region where there is haze in the cornea after PRK was performed and SMA+ myofibroblasts are present at higher density. However, some SMA+ myofibroblasts themselves produce IL-1α and/or IL-1β, suggesting that myofibroblast viability could also be regulated via autocrine mechanisms. PMID:20603114

  20. 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

  1. Large contiguous gene deletions in Sjögren-Larsson syndrome.

    Science.gov (United States)

    Engelstad, Holly; Carney, Gael; S'aulis, Dana; Rise, Janae; Sanger, Warren G; Rudd, M Katharine; Richard, Gabriele; Carr, Christopher W; Abdul-Rahman, Omar A; Rizzo, William B

    2011-11-01

    Sjögren-Larsson syndrome (SLS) is an autosomal recessive disorder characterized by ichthyosis, mental retardation, spasticity and mutations in the ALDH3A2 gene for fatty aldehyde dehydrogenase, an enzyme that catalyzes the oxidation of fatty aldehyde to fatty acid. More than 70 mutations have been identified in SLS patients, including small deletions or insertions, missense mutations, splicing defects and complex nucleotide changes. We now describe 2 SLS patients whose disease is caused by large contiguous gene deletions of the ALDH3A2 locus on 17p11.2. The deletions were defined using long distance inverse PCR and microarray-based comparative genomic hybridization. A 24-year-old SLS female was homozygous for a 352-kb deletion involving ALDH3A2 and 4 contiguous genes including ALDH3A1, which codes for the major soluble protein in cornea. Although lacking corneal disease, she showed severe symptoms of SLS with uncommon deterioration in oral motor function and loss of ambulation. The other 19-month-old female patient was a compound heterozygote for a 1.44-Mb contiguous gene deletion and a missense mutation (c.407C>T, P136L) in ALDH3A2. These studies suggest that large gene deletions may account for up to 5% of the mutant alleles in SLS. Geneticists should consider the possibility of compound heterozygosity for large deletions in patients with SLS and other inborn errors of metabolism, which has implications for carrier testing and prenatal diagnosis.

  2. Effective spherical aberration of the cornea as a quantitative descriptor in corneal topography.

    Science.gov (United States)

    Seiler, T; Reckmann, W; Maloney, R K

    1993-01-01

    Following excimer laser photorefractive keratectomy and other refractive surgical procedures, complaints of halos, glare, and monocular diplopia are common. These procedures increase the asphericity of the cornea, which may cause the optical distortions. We used ray tracing techniques to estimate the longitudinal monochromatic aberration of the cornea from the measured corneal topography (effective spherical aberration) in 15 normal eyes with varying degrees of astigmatism and in ten eyes after photorefractive keratectomy. Best spherical corrected visual acuity in the astigmatic eyes was highly correlated with effective spherical aberration (r = -0.9527, P < .001). In the eyes that had photorefractive keratectomy, the effective spherical aberration was highly correlated with measured glare visual acuity (r = 0.875, P < .002). These results suggest that effective spherical aberration is a valuable topographic measure that provides information about the optical performance of aspheric corneas.

  3. Study of noncontact air-puff applanation tonometry IOP measurement on irregularly-shaped corneas

    Science.gov (United States)

    Wang, Wai W.; Wang, Kuo-Jen; Tsai, Che-Liang; Wang, I.-Jong

    2017-04-01

    Abnormal corneas with corneal tissue defects like ulceration, melting, laceration, thinning scar, keratoconus etc., poses special challenges for ophthalmologist to measure intraocular pressure (IOP) correctly using air-puff noncontact applanation tonometry. Here, we propose an novel model, Abnormal Applanation IOP Model (AAIOP), to simulate IOP in these abnormal corneas on an air-puff noncontact applanation tonometry system, and the simulated IOP results are correctly fit in those of IOP measured database on human eyes of 91,024 patients (174,666 eyes)1). Our simulated IOP indicates that every 10 μm of central corneal thickness change results in 0.36 mmHg of IOP change. Using our simulation model, the IOP on abnormal eyes with irregularly-shaped corneas can be correctly expected and reported.

  4. Holographic interferometry of intact and radially incised human eye-bank corneas.

    Science.gov (United States)

    Smolek, M K

    1994-05-01

    Many methods to measure corneal elasticity destroy the tissue and thereby produce erroneous results. Holographic interferometry, a highly precise nondestructive optical comparison technique, was used to evaluate corneal elasticity of intact eye-bank eyes. A double-pulse holographic interferometer operating at 632.8 nm was used to measure corneal deformation in 20 whole-globe eyes from donors 45 to 83 years of age for intraocular pressures from 16 mm Hg to 21 mm Hg. Stress was computed from LaPlace's law, and arc length strain was derived from z-axis distention of the central cornea. The stress-strain relationship in the normal physiological range of intraocular pressure was linear with a Young's elastic modulus of 1.03 gigapascals for the central cornea (r = 0.999). During interferometry of radial keratotomy of the cornea, interference fringe patterns developed in association with each incision as it was made. When four incisions were placed deep along each of the primary semimeridians, the fringe pattern developed as expected, based on current keratotomy models. When incisions were shallow (approximately 50% depth) and placed asymmetrically along the nasal, temporal, and superior semimeridians, the resulting surface strain was symmetrical about the central cornea, forming an annular pattern of interference fringes. These results indicate that when the cornea was stressed at physiological pressures as part of the intact whole globe, it was less elastic than excised corneal tissue tested by strip extensiometry. Radially incised corneas demonstrated strain patterns suggestive of inherent structural anisotropy with a possible inferior quadrant weakness.

  5. 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.

  6. [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.

  7. [Pathological changes of the cornea in rabbits with hyphema and concurrent ocular hypertension].

    Science.gov (United States)

    Wang, Feng-yun; Lu, Xiao-he; Zhang, Cai-xia; Bai, Lang; Zhang, Jing; Zhong, Yan-yan; Wang, Shuang-shuang

    2010-03-01

    To evaluate the impact of hyphema secondary to high intraocular pressure on corneal pathology in rabbits. Thirty adult New Zealand rabbit were randomized into 3 equal groups, and in each rabbit, one eye served as the experimental eye with the other as the control eye. In the experimental eye, autoblood was injected into the anterior chamber to induce high intraocular pressure maintained for 3, 5, or 8 days. Only saline was injected into the control eye. After the injections, the cornea was observed with slit-lamp microscopy, and at 3, 5, or 8 days, the experimental and control eyes were taken from the 3 groups for microscopic examination of the corneas to detect the occurrence of cornea bloodstain with prolonged high intraocular pressure. Corneal edema, elastic fibers changes, growth of new blood vessels, changes of eosinophils, fibroblasts, lymphocytes and plasma cells, as well as the pathological changes of the corneal layers were observed and compared between the experimental and control eyes. Maintenance of high intraocular pressure for 8 days resulted in the most severe corneal edema and thickening, and histopathologically, the corneal stroma showed widened space between the elastic fibers and obvious fiber distortion. Neovascularization was seen in the marginal cornea where eosinophil infiltration occurred with a small number of lymphocytes, plasma cells and fiber cells. All the three groups showed more obvious edema in the posterior than in the anterior cornea. Prolonged hyphema with ocular hypertension results in aggravation of corneal edema, and corneal blood staining does not occur until 8 days of high intraocular pressure but corneal elastic fiber disruption can be seen, suggesting the impending irreversible pathological changes of cornea.

  8. 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.

  9. Morphological characterization of keratoconus-affected human corneas by SHG imaging and correlation analysis

    Science.gov (United States)

    Mercatelli, R.; Ratto, F.; Tatini, F.; Rossi, F.; Menabuoni, L.; Nicoletti, R.; Pini, R.; Pavone, Frederick; Cicchi, R.

    2016-03-01

    Keratoconus is an ophthalmic disease in which the cornea acquires an abnormal conical shape that prevents the correct focusing on the retina, causing visual impairment. The late diagnosis of keratoconus is among the principal causes of corneal transplantation surgery. In this study, we characterize the morphology of keratoconic corneas by means of the correlation of SHG images, finding that keratoconus can be diagnosed by analyzing the inclination of lamellae below Bowman's membrane. In addition, imaging performed with both sagittal and "en face" geometry demonstrated that this morphological features can be highlighted both ex vivo and in vivo.

  10. Second harmonic generation imaging of collagen fibrils in cornea and sclera

    Science.gov (United States)

    Han, Meng; Giese, Günter; Bille, Josef F.

    2005-07-01

    Collagen, as the most abundant protein in the human body, determines the unique physiological and optical properties of the connective tissues including cornea and sclera. The ultrastructure of collagen, which conventionally can only be resolved by electron microscopy, now can be probed by optical second harmonic generation (SHG) imaging. SHG imaging revealed that corneal collagen fibrils are regularly packed as a polycrystalline lattice, accounting for the transparency of cornea. In contrast, scleral fibrils possess inhomogeneous, tubelike structures with thin hard shells, maintaining the high stiffness and elasticity of the sclera.

  11. 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.

  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. Otodental syndrome

    Directory of Open Access Journals (Sweden)

    Bloch-Zupan Agnès

    2006-03-01

    Full Text Available Abstract The otodental syndrome also named otodental dysplasia, is characterised by a striking dental phenotype known as globodontia, associated with sensorineural high frequency hearing loss and eye coloboma. Globodontia occurs in both primary and permanent dentition, affecting canine and molar teeth (i.e. enlarged bulbous malformed posterior teeth with almost no discernable cusps or grooves. The condition appears to be inherited in an autosomal dominant mode, although sporadic cases have been reported. It is a rare disease, a few families have been described in the literature. In the British family, the locus for oculo-oto-dental syndrome was mapped to 20q13.1 within a 12-cM critical chromosomal region. Dental management is complex, interdisciplinary and will include regular follow up, scheduled teeth extraction and orthodontic treatment. Hearing checks and, if necessary, hearing aids are mandatory, as well as eye examination and ad hoc treatment if necessary.

  14. Epibulbar complex choristoma and hemimegalencephaly in linear sebaceous naevus syndrome.

    Science.gov (United States)

    Park, J M; Kim, D S; Kim, J; Lee, M G; Oh, S H

    2009-12-01

    Epidermal naevus syndrome is a group of congenital syndromes comprising epidermal naevi associated with a variety of developmental abnormalities of the ocular, nervous, skeletal, cardiovascular and urogenital systems. We describe a case of an 8-month-old boy with a brown alopecic plaque on his face and scalp and a vascularized epibulbar mass involving the entire cornea, which had been present since birth. Histopathological examination identified sebaceous naevus in combination with complex choristoma. Magnetic resonance imaging of the brain showed hemimegalencephaly.

  15. Variation at the TERT locus and predisposition for cancer.

    Science.gov (United States)

    Baird, Duncan M

    2010-05-18

    Telomerase and the control of telomere length are intimately linked to the process of tumourigenesis in humans. Here I review the evidence that variation at the 5p15.33 locus, which contains the TERT gene (encoding the catalytic subunit of telomerase), might play a role in the determination of cancer risk. Mutations in the coding regions of TERT can affect telomerase activity and telomere length, and create severe clinical phenotypes, including bone marrow failure syndromes and a substantive increase in cancer frequency. Variants within the TERT gene have been associated with increased risk of haematological malignancies, including myelodysplastic syndrome and acute myeloid leukaemia as well as chronic lymphocytic leukaemia. Furthermore, there is good evidence from a number of independent genome-wide association studies to implicate variants at the 5p15.33 locus in cancer risk at several different sites: lung cancer, basal cell carcinoma and pancreatic cancer show strong associations, while bladder, prostate and cervical cancer and glioma also show risk alleles in this region. Thus, multiple independent lines of evidence have implicated variation in the TERT gene as a risk factor for cancer. The mechanistic basis of these risk variants is yet to be established; however, the basic biology suggests that telomere length control is a tantalising candidate mechanism underlying cancer risk.

  16. Homozygosity mapping of the gene for Chediak-Higashi syndrome to chromosome 1q42-q44 in a segment of conserved synteny that includes the mouse beige locus (bg)

    Energy Technology Data Exchange (ETDEWEB)

    Fukai, Kazuyoshi; Oh, Jangsuk; Karim, M.A. [Univ. of Wisconsin Medical School, Madison, WI (United States)] [and others

    1996-09-01

    Chediak-Higashi syndrome (CHS) is an autosomal recessive disorder characterized by hypopigmentation or oculocutaneous albinism and severe immunologic deficiency with neutropenia and lack of natural killer (NK) cell function. Most patients die in childhood from pyogenic infections or an unusual lymphoma-like condition. A hallmark of the disorder is giant inclusion bodies seen in all granule-containing cells, including granulocytes, lymphocytes, melanocytes, mast cells, and neurons. Similar ultrastructural abnormalities occur in the beige mouse, which thus has been suggested to be homologous to human CHS. High-resolution genetic mapping has indicated that the bg gene region of mouse chromosome 13 is likely homologous to the distal portion of human chromosome 1q. Accordingly, we carried out homozygosity mapping using markers derived from distal human chromosome 1q in four inbred families or probands with CHS. Our results indicate that the human CHS gene maps to an 18.8-cM interval in chromosome segment 1q42-q44 and that human CHS therefore is very likely homologous to mouse bg. 43 refs., 2 figs.

  17. Effect of topical fluoroquinolones on the expression of matrix metalloproteinases in the cornea

    OpenAIRE

    O'Brien Terrence P; Song Jae K; Hakim Melinda A; Reviglio Victor E

    2003-01-01

    Abstract Background Matrix metalloproteinases play an important role in extracellular matrix deposition and degradation. Based on previous clinical observations of corneal perforations during topical fluoroquinolone treatment, we decided to evaluate the comparative effects of various fluoroquinolone eye drops on the expression of matrix metalloproteinases (MMPs) in cornea. Methods Eighty female Lewis rats were divided into two experimental groups: intact and wounded corneal epithelium. Unifor...

  18. [Simple keratectomy in band-shaped degeneration of the cornea (author's transl)].

    Science.gov (United States)

    Kenyeres, P

    1980-01-01

    In a case of band-shaped keratopathy chemical solution of the opacity failed but it proved easy to remove Bowman's membrane by grasping it with a forceps and pulling it off. As a result the cornea became clear and vision improved up to 6/7ths.

  19. 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.

  20. 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 conjun

  1. Influx of immunoglobulins from the vascular compartment into a grafted cornea

    NARCIS (Netherlands)

    VanDerVeen, G; Broersma, L; Bruyne, [No Value; Verhagen, C; VanRij, G; VanDerGaag, R; Ruijter, J

    1997-01-01

    Purpose. To determine the effect of a fresh corneal wound or a healed corneal Methods. F344 rats were immunized with human serum albumin (HSA) 1 week before an autologous rotational keratoplasty of the right cornea or 1 year after an autograft was performed. One group of rats also was treated with g

  2. 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.

  3. Model of Mass and Heat Transfer during Vacuum Freeze-Drying for Cornea

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    Zou Huifen

    2012-01-01

    Full Text Available Cornea is the important apparatus of organism, which has complex cell structure. Heat and mass transfer and thermal parameters during vacuum freeze-drying of keeping corneal activity are studied. The freeze-drying cornea experiments were operated in the homemade vacuum freeze dryer. Pressure of the freeze-drying box was about 50 Pa and temperature was about −10°C by controlled, and operating like this could guarantee survival ratio of the corneal endothelium over the grafting normal. Theory analyzing of corneal freeze-drying, mathematical model of describing heat and mass transfer during vacuum freeze-drying of cornea was established. The analogy computation for the freeze-drying of cornea was made by using finite-element computational software. When pressure of the freeze-drying box was about 50 Pa and temperature was about −10°C, time of double-side drying was 170 min. In this paper, a moving-grid finite-element method was used. The sublimation interface was tracked continuously. The finite-element mesh is moved continuously such that the interface position always coincides with an element node. Computational precision was guaranteed. The computational results were agreed with the experimental results. It proved that the mathematical model was reasonable. The finite-element software is adapted for calculating the heat and mass transfer of corneal freeze-drying.

  4. Shape of the anterior cornea : Comparison of height data from 4 corneal topographers

    NARCIS (Netherlands)

    de Jong, Tim; Sheehan, Matthew T.; Dubbelman, Michiel; Koopmans, Steven A.; Jansonius, Nomdo M.

    2013-01-01

    PURPOSE: To compare the ability of clinical corneal topographers to describe the shape of the anterior cornea for optical modeling. SETTING: University Medical Center Groningen, Groningen, Netherlands. DESIGN: Cross-sectional study. METHODS: The anterior corneal shape of healthy subjects was assesse

  5. Spectroscopic measurements and terahertz imaging of the cornea using a rapid scanning terahertz time domain spectrometer

    Science.gov (United States)

    Wen-Quan, Liu; Yuan-Fu, Lu; Guo-Hua, Jiao; Xian-Feng, Chen; Zhi-Sheng, Zhou; Rong-Bin, She; Jin-Ying, Li; Si-Hai, Chen; Yu-Ming, Dong; Jian-Cheng, Lv

    2016-06-01

    Spectroscopic measurements and terahertz imaging of the cornea are carried out by using a rapid scanning terahertz time domain spectroscopy (THz-TDS) system. A voice coil motor stage based optical delay line (VCM-ODL) is developed to provide a rather simple and robust structure with both the high scanning speed and the large delay length. The developed system is used for THz spectroscopic measurements and imaging of the corneal tissue with different amounts of water content, and the measurement results show the consistence with the reported results, in which the measurement time using VCM-ODL is a factor of 360 shorter than the traditional motorized optical delay line (MDL). With reducing the water content a monotonic decrease of the complex permittivity of the cornea is observed. The two-term Debye relaxation model is employed to explain our experimental results, revealing that the fast relaxation time of a dehydrated cornea is much larger than that of a hydrated cornea and its dielectric behavior can be affected by the presence of the biological macromolecules. These results demonstrate that our THz spectrometer may be a promising candidate for tissue hydration sensing and practical application of THz technology. Project supported by the National Natural Science Foundation of China (Grant No. 61205101), the Shenzhen Municipal Research Foundation, China (Grant Nos. GJHZ201404171134305 and JCYJ20140417113130693), and the Marie Curie Actions-International Research Staff Exchange Scheme (IRSES) (Grant No. FP7 PIRSES-2013-612267).

  6. Pretreatment methods to improve nerve immunostaining in corneas from long-term fixed embryonic quail eyes

    Science.gov (United States)

    Barrett, J. E.; Wells, D. C.; Conrad, G. W.

    1999-01-01

    Pretreatment methods were used to improve neurofilament immunostaining in corneas from embryonic day 16 Japanese quail corneas that had been stored in fixative solution for several months. A sequential combination of the following three pretreatments: brief microwave heating in saline, followed by extraction with sodium dodecyl sulfate (SDS) at 37 degrees C, followed by digestion with hyaluronidase at 37 degrees C, produced significantly increased antibody staining of corneal neurofilament proteins, compared with embryonic corneas subjected to no prior pretreatments or to single or two-step protocols. After applying the sequence of all three pretreatments, darkest nerve staining and increased numbers of fine branches were observed, together with lower background staining. Thus, the result of applying the three-step pretreatment sequence is better than that of applying any of its component single pretreatments or even combinations of any two of them. These findings therefore suggest that each of these three pretreatments causes a unique effect, beneficial to immunostaining of neurofilament proteins, and that their individual effects are independent and additive. In addition to embryonic corneas, the three-step procedure also may be useful for immunostaining of nerves in other very delicate, highly-hydrated tissues containing an abundance of extracellular matrix.

  7. Bacterial cellulose and bacterial cellulose/polycaprolactone composite as tissue substitutes in rabbits' cornea

    Directory of Open Access Journals (Sweden)

    Rodrigo V. Sepúlveda

    Full Text Available ABSTRACT: In order to test the performance of bacterial cellulose/polycaprolactone composite (BC/PCL and pure bacterial cellulose (BC as tissue substitutes in rabbits' cornea, a superficial ulcer containing 5mm in diameter and 0.2mm deep was made in the right cornea of 36 rabbits, then a interlayer pocket was created from the basis of this ulcer. Twelve rabbits received BC/PCL membrane and 12 were treated with BC membranes, both membranes with 8mm in diameter. The remaining rabbits received no membrane constituting the control group. The animals were clinically followed up for 45 days. Three animals of each group were euthanized at three, seven, 21, and 45 days after implantation for histological examination of the cornea along with the implant. Clinical observation revealed signs of moderate inflammatory process, decreasing from day 20th in the implanted groups. Histology showed absence of epithelium on the membranes, fibroplasia close to the implants, lymph inflammatory infiltrate with giant cells, collagen disorganization, with a predominance of immature collagen fibers in both groups with implants. Although inflammatory response is acceptable, the membranes used does not satisfactorily played the role of tissue substitute for the cornea during the study period.

  8. Impression cytology and in vivo confocal microscopy in corneas with total limbal stem cell deficiency

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    Aline Lütz de Araújo

    2013-10-01

    Full Text Available PURPOSES: To describe corneal changes seen on in vivo confocal microscopy in patients with total limbal stem cell deficiency and to correlate them with cytological findings. METHODS: A prospective case series including 13 eyes (8 patients with total limbal deficiency was carried out. Stem cell deficiency was diagnosed clinically and by corneal impression cytology. Confocal images of the central cornea were taken with the Heidelberg Retina Tomograph II, Rostock Corneal Module (Heidelberg Engineering, Heidelberg, Germany. RESULTS: Impression cytology of the cornea revealed conjunctival epithelial cells and goblet cells in all cases. In vivo confocal microscopy showed disruption of normal layers of the corneal epithelium in all eyes. Confocal images showed cells with characteristics of conjunctival epithelium at the cornea in 76.9% of the total. These findings on confocal microscopy were compatible to limbal stem cell deficiency. Additionally, goblet cells, squamous metaplasia, inflammatory cells and dendritic cells were observed. The sub-basal nerve plexus was not identified in any of the corneas. Corneal neovessels were observed at the epithelium and stroma. All cases showed diffuse hyper-reflective images of the stroma corresponding to opacity of the tissue. CONCLUSIONS: Limbal stem cell deficiency had been confirmed by impression cytology in all cases, and 76.9% of the cases could also be diagnosed by in vivo confocal microscopy through the conjunctival epithelial cell visualization on the corneal surface. Frequent confocal microscopy findings were abnormal cells at the cornea (conjunctival epithelial, goblet and inflammatory cells, corneal neovessels and diffuse hyper-reflection of the stroma.

  9. Assessment of anti-scarring therapies in ex vivo organ cultured rabbit corneas.

    Science.gov (United States)

    Sriram, Sriniwas; Gibson, Daniel J; Robinson, Paulette; Pi, Liya; Tuli, Sonal; Lewin, Alfred S; Schultz, Gregory

    2014-08-01

    The effects of a triple combination of siRNAs targeting key scarring genes were assessed using an ex vivo organ culture model of excimer ablated rabbit corneas. The central 6 mm diameter region of fresh rabbit globes was ablated to a depth of 155 microns with an excimer laser. Corneas were excised, cultured at the air-liquid interface in defined culture medium supplemented with transforming growth factor beta 1 (TGFB1), and treated with either 1% prednisolone acetate or with 22.5 μM cationic nanoparticles complexed with a triple combination of siRNAs (NP-siRNA) targeting TGFB1, TGFB Receptor (TGFBR2) and connective tissue growth factor (CTGF). Scar formation was measured using image analysis of digital images and levels of smooth muscle actin (SMA) were assessed in ablated region of corneas using qRT-PCR and immunostaining. Ex vivo cultured corneas developed intense haze-like scar in the wounded areas and levels of mRNAs for pro-fibrotic genes were significantly elevated 3-8 fold in wounded tissue compared to unablated corneas. Treatment with NP-siRNA or steroid significantly reduced quantitative haze levels by 55% and 68%, respectively, and reduced SMA mRNA and immunohistostaining. This ex vivo corneal culture system reproduced key molecular patterns of corneal scarring and haze formation generated in rabbits. Treatment with NP-siRNAs targeting key scarring genes or an anti-inflammatory steroid reduced corneal haze and SMA mRNA and protein. Copyright © 2014 Elsevier Ltd. All rights reserved.

  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. Involvement of S100A4 in stromal fibroblasts of the regenerating cornea.

    Science.gov (United States)

    Ryan, David G; Taliana, Lavinia; Sun, Lijie; Wei, Zhi-Gang; Masur, Sandra K; Lavker, Robert M

    2003-10-01

    S100A4 is a member of the S100 family of calcium-binding proteins. Members of the S100 family have been implicated in a variety of cellular events, including growth, signaling, differentiation, and motility. It has been suggested that S100A4 modulates cell shape and motility by interacting with components of the cytoskeleton. In the present study, the distribution patterns of S100A4 were investigated in normal and regenerating mouse corneas. Rabbit cDNA libraries were prepared from cultures of corneal fibroblasts. S100A4 was identified as the most abundant message present. Expression of S100A4 in the cornea was determined using Northern blot analysis, in situ hybridization, and immunohistochemistry. Distribution patterns of S100A4 in primary corneal fibroblast cultures treated with either FGF-2/heparin or TGFbeta1 were analyzed by immunofluorescence. S100A4 mRNA was rarely detected in keratocytes or epithelial cells of the normal rabbit cornea. Likewise, S100A4 antigen was not found in normal mouse corneas. However, after removal of the corneal epithelium, fibroblasts are activated and had readily detectable S100A4 expression 6 days after wounding. In the in vitro equivalent of activated keratocytes, cultured rabbit corneal fibroblasts, S100A4 was restricted to the cytoplasm. In contrast, in cultures treated with TGFbeta1, which induces a myofibroblast phenotype, more than 90% of the cells showed a nuclear localization of S100A4. The findings show that S100A4 is expressed in the keratocyte phenotypes that appear in stromal tissue of corneas recovering from damage, the fibroblasts, and myofibroblasts. Its expression and distinct subcellular redistribution patterns suggest that S100A4 may be involved in the interconversions that occur between keratocytes, fibroblasts, and myofibroblasts during corneal wound healing.

  12. Expression of microsomal prostaglandin e synthase-1 in fibroblasts of rabbit alkali-burned corneas.

    Science.gov (United States)

    Kawamura, Aruha; Tatsuguchi, Atsushi; Ishizaki, Masamichi; Takahashi, Hiroshi; Fukuda, Yuh

    2008-12-01

    Prostaglandin E2 is related to wound healing. Three different prostaglandin E synthases have been identified: microsomal prostaglandin E synthase (mPGES)-1, mPGES-2, and cytosolic prostaglandin E synthase. This study examined mPGES-1 expression in the cornea during the reparative process that occurs after an alkali burn. mPGES-1 messenger RNA (mRNA) and protein expression levels were examined by reverse transcription-polymerase chain reaction and Western blot analysis. Localization of mPGES-1 mRNA was examined by in situ hybridization. Using immunostaining, the localization of mPGES-1, cyclooxygenase (COX)-2, and alpha-smooth muscle actin (alpha-SMA) protein was studied. Although mPGES-1 mRNA is expressed in normal cornea, after a corneal injury, a progressive increase of mPGES-1 mRNA occurs. In this study, 2-6 weeks after injury, mPGES-1 mRNA was detected in the stromal spindle cells. Western blot analysis also showed that mPGES-1 protein expression was observed in normal cornea, with an increase noted from 2 to 4 weeks after corneal injury. mPGES-1 immunoreactivity was negative in normal cornea; however, starting at 2 weeks after injury, positive staining of the stromal spindle cells was noted. Although COX-2 and alpha-SMA immunoreactivities were negative in the stroma of normal cornea, after injury, staining was observed in the stromal spindle cells. alpha-SMA-positive cells and myofibroblasts express mPGES-1 mRNA and protein, and in addition, mPGES-1 colocalized with COX-2, suggesting that myofibroblasts synthesize prostaglandin E2 and may act on and accelerate corneal wound healing.

  13. Variable depth thermal lesions in rabbit corneas using a tunable thulium fiber laser

    Science.gov (United States)

    Fried, Nathaniel M.; Noguera, Guillermo; Castro-Combs, Juan; Behrens, Ashley

    2007-02-01

    Laser-induced thermal changes in the cornea have been used clinically for refractive surgery. This study describes the creation of variable depth thermal lesions in the cornea using a tunable Thulium fiber laser. Thermal lesions were created in fresh rabbit corneas, ex vivo, at three different wavelengths (1873 nm, 1890 nm, and 1904 nm) (n=6 corneas each). All other laser parameters were kept fixed with power of 5.5 W, 25-ms exposure time, and 650-μm diameter spot, yielding a single pulse exposure of 138 mJ, and a fluence of 42 J/cm2. Optical coherence tomography (OCT) and histology were used to measure pre- and post-operative corneal thickness and lesion dimensions. OCT measurements of pre and post-operative corneal thickness and lesion depth (in microns) were: (1873 nm: 450+/-30, 801+/-95, 655+/-51), (1890 nm: 460+/-27, 618+/-70, 332+/-56), (1904 nm: 448+20, 550+/-42, 245+36), respectively. By comparison, histologic measurements were: (1873 nm: 470+25, 828+21, 540+/-31), (1890 nm: 457+/-13, 625+/-17, 350+/-43), (1904 nm: 465+/-40, 627+/-35, 239+/-23), respectively. OCT lesion depth measured 82%, 54%, and 45% of corneal thickness, compared to histologic analysis of 65%, 56%, and 38%. This is the first preliminary test of a compact and tunable Thulium fiber laser for creating variable depth thermal lesions in the cornea. The Thulium fiber laser may have potential use as a replacement for the Ho:YAG and diode lasers for thermal keratoplasty.

  14. 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.

  15. Harnessing of corneas captured and processed for transplantation in an ocular tissue bank of North-eastern Brazil

    Directory of Open Access Journals (Sweden)

    Izaura Luzia Silvério Freire

    Full Text Available The aim of this study was to describe the harnessing of corneas captured and processed for transplantation in an ocular tissue bank in north-eastern Brazil. This was a transverse and retrospective study, with a sample group of 612 individuals whose corneas were donated and captured between January/2007 and July/2012. This study was approved by the Research Ethics Committee under number 007.0.294.000-10, and research was based on an instrument consisting of social, demographic and clinical data of the donors. Of the 1209 corneas captured, 868 were used and 341 were discarded. Of the 612 donors, the corneas of 597 (97.5% were captured from both eyes, being that 423 (70.9% of these corneas were used. Further studies are required on the reasons for discarding corneas and clarifications as to the conduct of professionals when processing corneas, considering the increase in the quantity of donors and the elevated number of discarded ocular tissue.

  16. Should antibody to hepatitis B core antigen be tested in routine screening of donor corneas for transplant?

    Science.gov (United States)

    Mattern, R M; Cavanagh, H D

    1997-03-01

    A review of the literature on transfusion-transmitted infectious diseases shows that antibody to hepatitis B core antigen (anti-HBc) is not presently viewed as helpful for hepatitis C or hepatitis non-ABC screening of blood donors. Its utility as a screen for hepatitis B or human immunodeficiency virus-1 (HIV-1) is controversial among experts. We compare relevant aspects of the screening of blood donations and the screening of cornea transplant donors to assess implications for the screening of donor corneas. We conclude that there is not sufficient evidence to warrant introducing anti-HBc as a routine screening test for cornea donors.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. 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....... TGFBIp in corneas from individuals ranging from six months to 86 years of age was detected and quantified by immunoblotting. The level of TGFBIp in the cornea increases about 30% between 6 and 14 years of age, and adult corneas contain 0.7-0.8 microg TGFBIp per mg wet tissue. Two-dimensional (2-D...... of corneal TGFBIp suggests that TGFBIp may play a role in the postnatal development and maturation of the cornea. Furthermore, these observations may be relevant to the age at which mutant TGFBIp deposits in the cornea in those dystrophies caused by mutations in the transforming growth factor beta induced...

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

    Science.gov (United States)

    Mohan, Rajiv R; Sinha, Sunilima; Tandon, Ashish; Gupta, Rangan; Tovey, Jonathan C K; Sharma, Ajay

    2011-04-12

    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-treated and

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

    Directory of Open Access Journals (Sweden)

    Rajiv R Mohan

    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

  1. Investigation of the influence of riboflavin-UV induced crosslinking on the cornea in the experiment

    Directory of Open Access Journals (Sweden)

    S. I. Anisimov

    2012-01-01

    Full Text Available Purpose: Morphological examination of the efficiency of the influence of various doses of riboflavin-UV induced crosslinking on the state of the corneal stroma in experimental animals.Methods: In the work were used rabbits males breed Chinchilla mass of 1.5-2.0 kg. the experiment was conducted on 20 eyes of 10 animals, which performed the routine crosslinking. Experimental animals, depending on the power UV-laser irradiation, were divided into 4 groups: the animals of the 1 group with the minimum intensity of radiation (30 minutes, 0.27 J, animals 2 group with medium intensity of radiation (15 minutes, 0.34 J, animals 3 groups with high intensity of radiation (30 minutes, 0.34 J, the control group 4 (without UV-radiation. Date of dynamic observation of the experimental animals was 5 days, after which the animals were taken out of the experiment. Morphological investigations were carried out by means of light and electron microscopy.Results: In groups of experimental animals with the impact of riboflavin UV-radiation in the stroma of the cornea were found the appearance of the areas of cross-stitched collagen fibers and fibrils. In the zone of the crosslinking were found activated keratoblasts.Near the membranes of these cells the contents of the vacuoles are released and filaments finish building of the collagen fibers. the epithelium of the corneas of all experimental animals recovered fully, with no morphological signs of endothelial damage has been found. Electron-microscopic investigation of stroma of corneas of the experimental animals of the control group after the experiment showed the presence of keratocytes in an inactive form and collagen fibers of stroma, packed in the form of plates or beams with a characteristic orientation.Conclusion: Studies have shown that UV-irradiation of the cornea leads to the appearance of linking between the fibers of collagen and actively synthesizing cells in the stroma of the cornea, which points to a

  2. Investigation of the influence of riboflavin-UV induced crosslinking on the cornea in the experiment

    Directory of Open Access Journals (Sweden)

    S. I. Anisimov

    2014-07-01

    Full Text Available Purpose: Morphological examination of the efficiency of the influence of various doses of riboflavin-UV induced crosslinking on the state of the corneal stroma in experimental animals.Methods: In the work were used rabbits males breed Chinchilla mass of 1.5-2.0 kg. the experiment was conducted on 20 eyes of 10 animals, which performed the routine crosslinking. Experimental animals, depending on the power UV-laser irradiation, were divided into 4 groups: the animals of the 1 group with the minimum intensity of radiation (30 minutes, 0.27 J, animals 2 group with medium intensity of radiation (15 minutes, 0.34 J, animals 3 groups with high intensity of radiation (30 minutes, 0.34 J, the control group 4 (without UV-radiation. Date of dynamic observation of the experimental animals was 5 days, after which the animals were taken out of the experiment. Morphological investigations were carried out by means of light and electron microscopy.Results: In groups of experimental animals with the impact of riboflavin UV-radiation in the stroma of the cornea were found the appearance of the areas of cross-stitched collagen fibers and fibrils. In the zone of the crosslinking were found activated keratoblasts.Near the membranes of these cells the contents of the vacuoles are released and filaments finish building of the collagen fibers. the epithelium of the corneas of all experimental animals recovered fully, with no morphological signs of endothelial damage has been found. Electron-microscopic investigation of stroma of corneas of the experimental animals of the control group after the experiment showed the presence of keratocytes in an inactive form and collagen fibers of stroma, packed in the form of plates or beams with a characteristic orientation.Conclusion: Studies have shown that UV-irradiation of the cornea leads to the appearance of linking between the fibers of collagen and actively synthesizing cells in the stroma of the cornea, which points to a

  3. Measurement of quantitative viscoelasticity of bovine corneas based on lamb wave dispersion properties.

    Science.gov (United States)

    Zhang, Xinyu; Yin, Yin; Guo, Yanrong; Fan, Ning; Lin, Haoming; Liu, Fulong; Diao, Xianfen; Dong, Changfeng; Chen, Xin; Wang, Tianfu; Chen, Siping

    2015-05-01

    The viscoelastic properties of the human cornea can provide valuable information for clinical applications such as the early detection of corneal diseases, better management of corneal surgery and treatment and more accurate measurement of intra-ocular pressure. However, few techniques are capable of quantitatively and non-destructively assessing corneal biomechanics in vivo. The cornea can be regarded as a thin plate in which the vibration induced by an external vibrator propagates as a Lamb wave, the properties of which depend on the thickness and biomechanics of the tissue. In this study, pulses of ultrasound radiation force with a repetition frequency of 100 or 200 Hz were applied to the apex of corneas, and the linear-array transducer of a SonixRP system was used to track the tissue motion in the radial direction. Shear elasticity and viscosity were estimated from the phase velocities of the A0 Lamb waves. To assess the effectiveness of the method, some of the corneas were subjected to collagen cross-linking treatment, and the changes in mechanical properties were validated with a tensile test. The results indicated that the shear modulus was 137 ± 37 kPa and the shear viscosity was 3.01 ± 2.45 mPa · s for the group of untreated corneas and 1145 ± 267 kPa and was 0.16 ± 0.11 mPa · s for the treated group, respectively, implying a significant increase in elasticity and a significant decrease in viscosity after collagen cross-linking treatment. This result is in agreement with the results of the mechanical tensile test and with reports in the literature. This initial investigation illustrated the ability of this ultrasound-based method, which uses the velocity dispersion of low-frequency A0 Lamb waves, to quantitatively assess both the elasticity and viscosity of corneas. Future studies could discover ways to optimize this system and to determine the feasibility of using this method in clinical situations.

  4. Characterizing the effects of VPA, VC and RCCS on rabbit keratocytes onto decellularized bovine cornea.

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    Ying Dai

    Full Text Available To investigate the morphological and growth characteristics of rabbit keratocytes when cultured on decellularized cornea under simulate microgravity (SMG rotary cell culture system (RCCS and static culture or in plastic culture supplemented with small molecules of valproic acid (VPA and vitamin C (VC. Bovine corneas were firstly decellularized with Triton X-100 and NH(4OH and through short-term freezing process. Then cell count kit-8 (CCK-8 and flow cytometry were used to test the effects of VPA and VC on the proliferation, cell cycle and apoptosis of rabbit keratocytes. Hematoxylin-eosin (H&E staining and scanning electron microscopy (SEM imaging showed that cells were eliminated in the decellularized bovine corneas. The proliferation of cultured keratocytes was promoted by VPA and VC in the cell proliferation assay. VPA and VC moderately decreased the number of apoptotic cells and obviously promoted cell-cycle entrance of keratocytes. Rabbit keratocytes in plastic displayed spindle shape and rare interconnected with or without VPA and VC. Cells revealed dendritic morphology and reticular cellular connections when cultured on the carriers of decellularized corneas supplemented with VPA and VC even in the presence of 10% fetal bovine serum (FBS. When cultured in RCCS supplemented with VPA, VC and 10% FBS, keratocytes displayed round shape with many prominences and were more prone to grow into the pores of carriers with aggregation. Reverse transcription-polymerase chain reaction (RT-PCR analysis proved that the keratocytes cultured on decellularized bovine cornea under SMG with VPA and VC expressed keratocan and lumican. Keratocytes cultured on plastic expressed lumican but not keratocan. Immunofluorescence identification revealed that cells in all groups were positively immunostained for vimentin. Keratocytes on decellularized bovine cornea under SMG or in static culture were positively immunostained for keratocan and lumican. Thus, we

  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. Physicochemical properties of biodegradable polyvinyl alcohol-agar films from the red algae Hydropuntia cornea.

    Science.gov (United States)

    Madera-Santana, Tomás J; Robledo, Daniel; Freile-Pelegrín, Yolanda

    2011-08-01

    Agar obtained from the red alga Hydropuntia cornea was blended with polyvinyl alcohol (PVOH) in order to produce biodegradable films. In this study, we compare the properties of biopolymeric films formulated with agars extracted from H. cornea collected at different seasons (rainy and dry) in the Gulf of Mexico coast and PVOH as synthetic matrix. The films were prepared at different agar contents (0%, 25%, 50%, 75%, and 100%) and their optical, mechanical, thermal, and morphological properties analyzed. The tensile strength of PVOH-agar films increased when agar content was augmented. The formulation with 50% agar from rainy season (RS) had a significant higher tensile strength when compared to those from dry season (DS; p biodegradable packaging industry.

  7. Photodynamic therapy (ALA-PDT) in the treatment of pathological states of the cornea

    Science.gov (United States)

    Switka-Wieclawska, Iwona; Kecik, Tadeusz; Kwasny, Miroslaw; Graczyk, Alfreda

    2003-10-01

    Each year an increasing amount of research is published on the use of photodynamic therapy in medicine. The most recent research has focused mostly on the use of photosensitizer called vertoporphyrin (Visudyne) is the treatment of subretinal neovascularization in age-related macular degeneration (AMD) or myopia, following a substantial amount of ophthalmology research mostly experimental on the application of the method in diagnosis and treatment of some eye tumors. In the Department of Ophthalmology of Polish Medical University in Warsaw, PDT was used as supplementary method in a selected group of patients with chronic virus ulcer of the cornea and keratopathies. During the treatment 5-aminolevulinic acid (5-ALA) was applied in ointment form as a photosensitizer activated with light wave of 633 nm. It appears, on the basis of the results obtained, that photodynamic therapy (ALA-PDT) may become in the future a valuable supplement to the methods being used at the present treating pathological states of the cornea.

  8. Tectonic deep anterior lamellar keratoplasty in impending corneal perforation using cryopreserved cornea.

    Science.gov (United States)

    Jang, Ji Hye; Chang, Sung Dong

    2011-04-01

    We report a case of tectonic corneal transplantation for impending corneal perforation to preserve anatomic integrity using cryopreserved donor tissue. An 82-year-old woman exhibiting impending corneal perforation suffered from moderate ocular pain in the left eye for one week. After abnormal tissues around the impending perforation area were carefully peeled away using a Crescent blade and Vannas scissors, the patient received tectonic deep anterior lamellar keratoplasty using a cryopreserved cornea stored in Optisol GS® solution at -70℃ for four weeks. At six months after surgery, the cornea remained transparent and restored the normal corneal thickness. There were no complications such as corneal haze or scars, graft rejection, recurrent corneal ulcer, and postoperative rise of intraocular pressure. Cryopreserved donor lamellar tissue is an effective substitute in emergency tectonic lamellar keratoplasty, such as impending corneal perforation and severe necrotic corneal keratitis.

  9. A new optical system for 3-dimensional mapping of the cornea

    Science.gov (United States)

    Franco, Sandra; Almeida, José B.

    2007-07-01

    In this work the authors present an optical corneal tomographer that uses two Scheimpflug cameras attached to an innovative illumination system that allows a rotary scanning of the entire cornea. The measurements are made from corneal optical sections obtained by illumination with a collimated beam expanded in a fan by a small cylindrical lens. This lens is provided with motor driven rotation in order to perform automated rotary scan of the whole cornea. The authors expect to achieve a scanning speed that will allow producing complete tomography maps without consideration of eye movements. Two Scheimpflug cameras are used to capture the images of the optical sections. With this system it is possible to obtain 3-D representation of the corneal thickness as well as corneal topography. Maps of the corneal thickness and elevation maps are shown. As Scheimpflug cameras are used, it is expected to obtained data from the lens too.

  10. Collagens and proteoglycans of the cornea: importance in transparency and visual disorders.

    Science.gov (United States)

    Massoudi, Dawiyat; Malecaze, Francois; Galiacy, Stephane D

    2016-02-01

    The cornea represents the external part of the eye and consists of an epithelium, a stroma and an endothelium. Due to its curvature and transparency this structure makes up approximately 70% of the total refractive power of the eye. This function is partly made possible by the particular organization of the collagen extracellular matrix contained in the corneal stroma that allows a constant refractive power. The maintenance of such an organization involves other molecules such as type V collagen, FACITs (fibril-associated collagens with interrupted triple helices) and SLRPs (small leucine-rich proteoglycans). These components play crucial roles in the preservation of the correct organization and function of the cornea since their absence or modification leads to abnormalities such as corneal opacities. Thus, the aim of this review is to describe the different corneal collagens and proteoglycans by highlighting their importance in corneal transparency as well as their implication in corneal visual disorders.

  11. Sensitivity and rapidity of blood culture bottles in the detection of cornea organ culture media contamination by bacteria and fungi

    OpenAIRE

    Thuret, G; Carricajo, A.; Chiquet, C.; Vautrin, A C; Celle, N; Boureille, M; Acquart, S; Aubert, G.; Maugery, J; Gain, P.

    2002-01-01

    Aims: To test the bactericidal activity of standard organ culture medium, and to compare the sensitivity and rapidity of blood culture bottles with conventional microbiological methods for detection of bacteria and fungi inoculated in a standard cornea organ culture medium.

  12. Pseudoexfoliation syndrome: in vivo confocal microscopy analysis.

    Science.gov (United States)

    Martone, Gianluca; Casprini, Fabrizio; Traversi, Claudio; Lepri, Francesca; Pichierri, Patrizia; Caporossi, Aldo

    2007-08-01

    Pseudoexfoliation (PEX) syndrome is a common ocular disease that also affects the cornea. A case of clinical PEX syndrome, studied by in vivo corneal confocal microscopy is reported. The morphological analysis of the confocal images demonstrated hyper-reflective deposits and several dendritic cells in the basal epithelial layer. A fibrillar subepithelial structure was also found. The endothelial layer showed cell anomalies (polymegathism and pleomorphism) and hyper-reflective small endothelial deposits. Confocal microscopy is an in vivo imaging method that may provide new information on corneal alterations in PEX, and detect early corneal features.

  13. Keratoconus Screening Indices and Their Diagnostic Ability to Distinguish Normal From Ectatic Corneas.

    Science.gov (United States)

    Shetty, Rohit; Rao, Harsha; Khamar, Pooja; Sainani, Kanchan; Vunnava, Krishnapoojita; Jayadev, Chaitra; Kaweri, Luci

    2017-09-01

    To compare the diagnostic ability of 3 Scheimpflug devices in differentiating normal from ectatic corneas. Comparison of diagnostic instrument accuracy. This study included 42 normal, 37 subclinical keratoconic, and 51 keratoconic eyes seen in a tertiary eye care institute. Keratoconus screening indices were evaluated using the Pentacam (Oculus, Wetzlar, Germany), Galilei (Ziemer, Biel, Switzerland), and Sirius (Costruzione Strumenti Oftalmici, Florence, Italy). Sensitivity, specificity, and area under receiver operating characteristic curve (AUC) were calculated. Highest sensitivity (100%) to diagnose keratoconus was seen for 6 parameters on Pentacam and 1 on Galilei. None of the indices in Sirius reached 100% sensitivity. For subclinical keratoconus, the highest sensitivity (100%) was seen for 2 parameters on Pentacam but for none of them on Galilei and Sirius. All parameters were strong enough to differentiate keratoconus (AUC > 0.9). On comparing the best parameters of all 3 machines, the AUC of the Belin/Ambrosio enhanced ectasia total derivation (BAD-D) and the inferior-superior value (ISV) of Pentacam were statistically similar to that of the keratoconus prediction index (KPI) and keratoconus probability (Kprob) of Galilei (P = .27) and 4.5 mm root mean square per unit area (RMS/A) back of Sirius (P = .55). When differentiating subclinical from normal corneas, BAD-D was similar to the surface regularity index (SRI) of Galilei (P = .78) but was significantly greater than the 8 mm RMS/A back of Sirius (P = .002). Keratoconus indices measured by all 3 machines can effectively differentiate keratoconus from normal corneas. However, new cutoff values might be needed to differentiate subclinical from normal corneas. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. New insight into the shortening of the collagen fibril D-period in human cornea.

    Science.gov (United States)

    Jastrzebska, Maria; Tarnawska, Dorota; Wrzalik, Roman; Chrobak, Artur; Grelowski, Michal; Wylegala, Edward; Zygadlo, Dorota; Ratuszna, Alicja

    2017-02-01

    Collagen fibrils type I display a typical banding pattern, so-called D-periodicity, of about 67 nm, when visualized by atomic force or electron microscopy imaging. Herein we report on a significant shortening of the D-period for human corneal collagen fibrils type I (21 ± 4 nm) upon air-drying, whereas no changes in the D-period were observed for human scleral collagen fibrils type I (64 ± 4 nm) measured under the same experimental conditions as the cornea. It was also found that for the corneal stroma fixed with glutaraldehyde and air-dried, the collagen fibrils show the commonly accepted D-period of 61 ± 8 nm. We used the atomic force microscopy method to image collagen fibrils type I present in the middle layers of human cornea and sclera. The water content in the cornea and sclera samples was varying in the range of .066-.085. Calculations of the D-period using the theoretical model of the fibril and the FFT approach allowed to reveal the possible molecular mechanism of the D-period shortening in the corneal collagen fibrils upon drying. It was found that both the decrease in the shift and the simultaneous reduction in the distance between tropocollagen molecules can be responsible for the experimentally observed effect. We also hypothesize that collagen type V, which co-assembles with collagen type I into heterotypic fibrils in cornea, could be involved in the observed shortening of the corneal D-period.

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

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    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.

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

    Science.gov (United States)

    2015-10-01

    protein TNF -stimulating gene 6 (TSG-6). TSG-6 may modulate the excessive inflammatory response that exacerbates the injury to the cornea caused by...period. The inflammatory response as measured by biochemical markers correlated with concentration of NAOH applied and began within 2 hours of injury...Goal – Establish the appropriate conditions for testing TSG-6 Determine timing and patterns of cellular and cytokine inflammatory responses as a

  17. A Cornea Substitute Derived from Fish Scale: 6-Month Followup on Rabbit Model

    OpenAIRE

    Fei Yuan; Liyan Wang; Chien-Chen Lin; Cheng-Hung Chou; Lei Li

    2014-01-01

    A fish scale-derived cornea substitute (Biocornea) is proposed as an alternative for human donor corneal tissue. We adopt a regenerative medicine approach to design a primary alternative to the use of fish scale for restoring sight by corneal replacement. Biocornea with corneal multilayer arrangement collagen was implanted to rabbits by pocket implantation. Our study demonstrated the safety and detailed morphologic and physiologic results from the 6 months of followup of rabbit model. In the ...

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

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    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.

  19. Proteoglycan biosynthesis by human corneas from patients with types 1 and 2 macular corneal dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Midura, R.J.; Hascall, V.C.; MacCallum, D.K.; Meyer, R.F.; Thonar, E.J.; Hassell, J.R.; Smith, C.F.; Klintworth, G.K. (National Institute of Dental Research, Bethesda, MD (USA))

    1990-09-15

    Corneal buttons were obtained from patients with types 1 and 2 macular corneal dystrophy (MCD) and from control patients with Fuchs' dystrophy or keratoconus. Buttons were incubated for 20 h in the presence of (3H)glucosamine or (2-3H)mannose. Radiolabeled proteoglycans and lactosaminoglycan-glycoproteins (L-GPs) were purified using chromatography on Q-Sepharose, Superose 6, and octyl-Sepharose. They were identified using chondroitinase ABC, keratanase or endo-beta-galactosidase digestion, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis or Superose 6 chromatography. This study confirms previous reports that type 1 MCD corneas synthesize a normal dermatan sulfate-proteoglycan (DS-PG) and an abnormal keratan sulfate-proteoglycan (KS-PG). The data indicate that typ 1 MCD corneas synthesize L-GP instead of KS-PG. This L-GP has a core protein of similar hydrophobicity (elution from octyl-Sepharose) and nearly similar mass (42 kDa) as the core protein of the KS-PG. It has identical glycoconjugates as those of the KS-PG except that they lack sulfate. Thus, type 1 MCD fails to synthesize keratan sulfate as a result of a defect in a sulfotransferase specific for sulfating lactosaminoglycans. Further, proteoglycans synthesized by a cornea from a patient with type 2 MCD were studied. This cornea synthesized a normal ratio of KS-PG to DS-PG although net synthesis of proteoglycans was approximately 30% below normal. The KS-PG appeared normal whereas the DS-PG had dermatan sulfate chains that were approximately 40% shorter than normal.

  20. Demonstration of cornea Dua's layer at a deep anterior lamellar keratoplasty surgery

    OpenAIRE

    Yusuf Kocluk; Ayse Burcu; Emine Alyamac Sukgen

    2016-01-01

    The authors aimed to present a deep anterior lamellar keratoplasty (DALK) surgery case with mixed type bubble demonstrating Dua′s layer (DL). This was a reported case of DALK surgery. The authors encountered cornea DL structure at DALK surgery while cleaning the remaining stromal pieces. We also observed perforation in the central part of DL. However, DALK surgery could be completed. It is possible to encounter DL in a DALK surgery performed with mixed type big-bubble.

  1. Demonstration of cornea Dua′s layer at a deep anterior lamellar keratoplasty surgery

    Directory of Open Access Journals (Sweden)

    Yusuf Kocluk

    2016-01-01

    Full Text Available The authors aimed to present a deep anterior lamellar keratoplasty (DALK surgery case with mixed type bubble demonstrating Dua′s layer (DL. This was a reported case of DALK surgery. The authors encountered cornea DL structure at DALK surgery while cleaning the remaining stromal pieces. We also observed perforation in the central part of DL. However, DALK surgery could be completed. It is possible to encounter DL in a DALK surgery performed with mixed type big-bubble.

  2. Synthesis of type III collagen by fibroblasts from the embryonic chick cornea

    OpenAIRE

    1980-01-01

    Synthesis of collagen types I, II, III, and IV in cells from the embryonic chick cornea was studied using specific antibodies and immunofluorescence. Synthesis of radioactively labeled collagen types I and III was followed by fluorographic detection of cyanogen bromide peptides on polyacrylamide slab gels and by carboxymethylcellulose chromatography followed by disc gel electrophoresis. Type III collagen had been detected previously by indirect immunofluorescence in the corneal epithelial cel...

  3. Occurrence of viral DNA in paired samples of corneal rim and cornea preservation fluid.

    Science.gov (United States)

    Broniek, G; Langwińska-Wośko, E; Sybilska, M; Szaflik, J P; Przybylski, M; Wróblewska, M

    2017-04-01

    Corneal transplants have one of the highest success rates among all transplantological procedures. Corneas intended for transplantation are stored in a preservation fluid, which is then tested for bacterial and fungal infections. Among all analyses of infectious complications following corneal transplants, infections caused by bacteria or fungi are the most prominent. Surprisingly, however, apart from a few publications, there is a lack of data regarding the occurrence of viruses in donor corneas and the risk of transmitting these to their recipients. The intention of this research was therefore to determine the frequency with which human herpesvirus 1 (HHV-1), human herpesvirus 2 (HHV-2), and human adenovirus (HAdV) occur in transplanted corneal tissue, as well as in samples of preservation fluid. The study comprised 57 paired samples, with each pair consisting of a fragment of the corneal tissue remaining after its trepanation for transplantation surgery and a sample of corneal preservation fluid. Sample pairs were all tested for the presence of the DNA of three viruses (HHV-1, HHV-2, and HAdV) using real time PCR technique. Viral DNA was found in three of the tested corneas-HHV-1 DNA in one paired sample (1.8%) and adenovirus DNA in two single samples (3.5%). We postulate that virological testing of corneas for transplantation should be considered, particularly in the case of donors with increased risk factors for herpesvirus and adenovirus reactivation. J. Med. Virol. 89:732-736, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Locus of control and decision to abort.

    Science.gov (United States)

    Dixon, P N; Strano, D A; Willingham, W

    1984-04-01

    The relationship of locus of control to deciding on an abortion was investigated by administering Rotter's Locus of Control Scale to 118 women immediately prior to abortion and 2 weeks and 3 months following abortion. Subjects' scores were compared across the 3 time periods, and the abortion group's pretest scores were compared with those of a nonpregnant control, group. As hypothesized, the aborting group scored significantly more internal than the general population but no differences in locus of control were found across the 3 time period. The length of delay in deciding to abort an unwanted pregnancy following confirmation was also assessed. Women seeking 1st trimester abortions were divided into internal and external groups on the Rotter Scale and the lengths of delay were compared. The hypothesis that external scores would delay the decision longer than internal ones was confirmed. The results confirm characteristics of the locus of control construct and add information about personality characteristics of women undergoing abortion.

  5. Genetics Home Reference: Senior-Løken syndrome

    Science.gov (United States)

    ... R, Ghiggeri GM. Renal-retinal syndromes: association of retinal anomalies and recessive nephronophthisis in patients with homozygous deletion of the NPH1 locus. Am J Kidney Dis. 1998 Dec;32(6): ...

  6. Safety of cornea and iris in ocular surgery with 355-nm lasers.

    Science.gov (United States)

    Wang, Jenny; Chung, Jae Lim; Schuele, Georg; Vankov, Alexander; Dalal, Roopa; Wiltberger, Michael; Palanker, Daniel

    2015-09-01

    A recent study showed that 355-nm nanosecond lasers cut cornea with similar precision to infrared femtosecond lasers. However, use of ultraviolet wavelength requires precise assessment of ocular safety to determine the range of possible ophthalmic applications. In this study, the 355-nm nanosecond laser was evaluated for corneal and iris damage in rabbit, porcine, and human donor eyes as determined by minimum visible lesion (MVL) observation, live/dead staining of the endothelium, and apoptosis assay. Single-pulse damage to the iris was evaluated on porcine eyes using live/dead staining. In live rabbits, the cumulative median effective dose (ED50) for corneal damage was 231 J/cm2, as seen by lesion observation. Appearance of endothelial damage in live/dead staining or apoptosis occurred at higher radiant exposure of 287 J/cm2. On enucleated rabbit and porcine corneas, ED50 was 87 and 52 J/cm2, respectively, by MVL, and 241 and 160 J/cm2 for endothelial damage. In human eyes, ED50 for MVL was 110 J/cm2 and endothelial damage at 453 J/cm2. Single-pulse iris damage occurred at ED 50 of 208 mJ/cm2. These values determine the energy permitted for surgical patterns and can guide development of ophthalmic laser systems. Lower damage threshold in corneas of enucleated eyes versus live rabbits is noted for future safety evaluation.

  7. Surface modification of silicone rubber membrane by plasma induced graft copolymerization as artificial cornea.

    Science.gov (United States)

    Hsiue, G H; Lee, S D; Chang, P C

    1996-11-01

    In this study a highly biocompatible polymer membrane was prepared by surface modification. An artificial cornea was also developed for clinical applications. Silicone rubber (SR) membrane was grafted with hydrophilic monomers such as 2-hydroxyethyl methacrylate (HEMA) and acrylic acid by plasma induced grafted polymerization. Surface properties of the SR were characterized using secondary ions mass spectra, Fourier transform infrared/attenuated total reflection, and element spectra for chemical analysis. The corneal epithelial (CE) cell was cultured in vitro, and penetrating keratoplasty of albino rabbit cornea (in vivo) was performed to evaluate biological properties of modified SR membranes. The ability of the CE cell to attach onto various SR membranes was observed by inverted microscopy. The proliferation of CE cell was conducted in approximately 96 h. Experimental results indicated that the attachment and growth of CE onto SR-g-pHEMA (75 micrograms/ cm2) is enhanced. The morphologies of an attached CE cell are similar to those of a primary CE cell. In the in vivo study, the depth of anterior chamber was maintained 2 weeks after penetrating keratoplasty was performed with a SR grafted with pHEMA (210 micrograms/cm2). This phenomenon displayed a high biocompatibility of modified SR membrane with the CE cell. Furthermore, results in this study provide a valuable reference for application of the modified SR for an artificial cornea.

  8. Resazurin metabolism assay is a new sensitive alternative test in isolated pig cornea.

    Science.gov (United States)

    Perrot, Sébastien; Dutertre-Catella, Hélène; Martin, Chantal; Rat, Patrice; Warnet, Jean-Michel

    2003-03-01

    The main object of our study was to investigate whether the resazurin metabolism assay is a sensitive surfactant and alcohol toxicity test in isolated pig cornea and to compare this recently developed fluorometric assay with the data collected in the eye irritation reference chemical data bank. Resazurin is a substrate that changes color in response to metabolic activity. Isolated pig corneas were immersed for 10 min in surfactants and alcohol irritant solutions. After incubation, resorufin fluorescence was read and corneal viability was assessed. This corneal viability was compared with the maximal modified average score published in the report of ECETOC. This assay highlighted different concentration-dependent irritation potentials of the three surfactants tested, and the same results were obtained with corneas treated with the alcohols. We observed that the degree of surfactant- and alcohol-induced decrease in corneal viability, using the resazurin reduction test, was correlated with the in vivo irritancy measurements as determined by the Draize test and scored with the Modified Maximum Average Score (MMAS). This assay allowed us to classify the ocular irritancy of the tested surfactants and alcohols in the same ranking order as the Draize classification. Corneal viability measurement can be used as a potential alternative for the toxicological assessment of surfactants and alcohols. The nontoxic, nonradioactive resazurin metabolism assay allows rapid assessment of many samples with simple equipment and at reduced cost for continuous monitoring of corneal viability. This assay seems to be suitable as a toxicological screening test for eye irritation determination.

  9. Temperature limitation may explain the containment of the trophozoites in the cornea during Acanthamoeba castellanii keratitis.

    Science.gov (United States)

    Nielsen, Mattias Kiel; Nielsen, Kim; Hjortdal, Jesper; Sørensen, Uffe B Skov

    2014-12-01

    Acanthamoeba keratitis is a serious sight-threatening disease. The relatively low temperature of the cornea may explain why amoebic infections usually are localized in this tissue and rarely spread to other parts of the eye. In this study, the growth rate of the amoeba Acanthamoeba castellanii was examined at different temperatures. The aim was to establish the optimal growth temperature for A. castellanii and to examine the growth within the vicinity of the core body temperature. The growth rates of four clinical and two environmental strains of A. castellanii were estimated at different temperatures, and temperature limitations for the trophozoite stage was established. Movements influenced by temperature gradients were monitored for two clinical strains of A. castellanii. The highest growth rate for each of the six amoebic strains tested was found to be close to 32 °C. The growth of the trophozoites of all examined strains was greatly reduced or completely halted at temperatures above 36 °C and encysted at the elevated temperature. Thus, the optimal growth temperature for the four strains of A. castellanii is close to the surface temperature of the human cornea, while the higher body core-temperature induced encysting of the amoebae. This may explain why most amoebic eye infections are confined to the cornea.

  10. Blast Wave Dynamics at the Cornea as a Function of Eye Protection Form and Fit.

    Science.gov (United States)

    Williams, Steven T; Harding, Thomas H; Statz, J Keegan; Martin, John S

    2017-03-01

    A shock tube and anthropomorphic headforms were used to investigate eye protection form and fit using eyewear on the Authorized Protective Eyewear List in primary ocular blast trauma experiments. Time pressure recordings were obtained from highly linear pressure sensors mounted at the cornea of instrumented headforms of different sizes. A custom shock tube produced highly reliable shock waves and pressure recordings were collected as a function of shock wave orientation and protective eyewear. Eyewear protection coefficients were calculated as a function of a new metric of eyewear fit. In general, better protection was correlated with smaller gaps between the eyewear and face. For oblique angles, most spectacles actually potentiated the blast wave by creating higher peak pressures at the cornea. Installing foam around the perimeter of the spectacle lens to close the gap between the lens and face resulted in significantly lower pressure at the cornea. In conclusion, current eye protection, which was designed to reduce secondary and tertiary blast injuries, provides insufficient protection against primary blast injury. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  11. 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.

  12. A Cornea Substitute Derived from Fish Scale: 6-Month Followup on Rabbit Model

    Directory of Open Access Journals (Sweden)

    Fei Yuan

    2014-01-01

    Full Text Available A fish scale-derived cornea substitute (Biocornea is proposed as an alternative for human donor corneal tissue. We adopt a regenerative medicine approach to design a primary alternative to the use of fish scale for restoring sight by corneal replacement. Biocornea with corneal multilayer arrangement collagen was implanted to rabbits by pocket implantation. Our study demonstrated the safety and detailed morphologic and physiologic results from the 6 months of followup of rabbit model. In the peripheral Biocornea, the collagen fibrils were arranged in reticular fashion. Slit lamp examination showed that haze and an ulcer were not observed in all groups at 3 months postoperatively while all corneas with Biocornea were clear at both 3 months and 6 months postoperatively. The interface of Biocornea and stromal tissue were filled successfully and without observable immune cells at postoperative day 180. Moreover, the Biocornea was not dissolved and degenerated but remained transparent and showed no apparent fragmentation. Our study demonstrated that the Biocornea derived from fish scale as a good substitute had high biocompatibility and support function after a long-term evaluation. This revealed that the new approach of using Biocornea may yield an ideal artificial cornea substitute for long-term inlay placement.

  13. Characterization of tissue-engineered posterior corneas using second- and third-harmonic generation microscopy.

    Directory of Open Access Journals (Sweden)

    Louis Jay

    Full Text Available Three-dimensional tissues, such as the cornea, are now being engineered as substitutes for the rehabilitation of vision in patients with blinding corneal diseases. Engineering of tissues for translational purposes requires a non-invasive monitoring to control the quality of the resulting biomaterial. Unfortunately, most current methods still imply invasive steps, such as fixation and staining, to clearly observe the tissue-engineered cornea, a transparent tissue with weak natural contrast. Second- and third-harmonic generation imaging are well known to provide high-contrast, high spatial resolution images of such tissues, by taking advantage of the endogenous contrast agents of the tissue itself. In this article, we imaged tissue-engineered corneal substitutes using both harmonic microscopy and classic histopathology techniques. We demonstrate that second- and third-harmonic imaging can non-invasively provide important information regarding the quality and the integrity of these partial-thickness posterior corneal substitutes (observation of collagen network, fibroblasts and endothelial cells. These two nonlinear imaging modalities offer the new opportunity of monitoring the engineered corneas during the entire process of production.

  14. Characterization of tissue-engineered posterior corneas using second- and third-harmonic generation microscopy.

    Science.gov (United States)

    Jay, Louis; Bourget, Jean-Michel; Goyer, Benjamin; Singh, Kanwarpal; Brunette, Isabelle; Ozaki, Tsuneyuki; Proulx, Stéphanie

    2015-01-01

    Three-dimensional tissues, such as the cornea, are now being engineered as substitutes for the rehabilitation of vision in patients with blinding corneal diseases. Engineering of tissues for translational purposes requires a non-invasive monitoring to control the quality of the resulting biomaterial. Unfortunately, most current methods still imply invasive steps, such as fixation and staining, to clearly observe the tissue-engineered cornea, a transparent tissue with weak natural contrast. Second- and third-harmonic generation imaging are well known to provide high-contrast, high spatial resolution images of such tissues, by taking advantage of the endogenous contrast agents of the tissue itself. In this article, we imaged tissue-engineered corneal substitutes using both harmonic microscopy and classic histopathology techniques. We demonstrate that second- and third-harmonic imaging can non-invasively provide important information regarding the quality and the integrity of these partial-thickness posterior corneal substitutes (observation of collagen network, fibroblasts and endothelial cells). These two nonlinear imaging modalities offer the new opportunity of monitoring the engineered corneas during the entire process of production.

  15. Fractal analysis of AFM images of the surface of Bowman's membrane of the human cornea.

    Science.gov (United States)

    Ţălu, Ştefan; Stach, Sebastian; Sueiras, Vivian; Ziebarth, Noël Marysa

    2015-04-01

    The objective of this study is to further investigate the ultrastructural details of the surface of Bowman's membrane of the human cornea, using atomic force microscopy (AFM) images. One representative image acquired of Bowman's membrane of a human cornea was investigated. The three-dimensional (3-D) surface of the sample was imaged using AFM in contact mode, while the sample was completely submerged in optisol solution. Height and deflection images were acquired at multiple scan lengths using the MFP-3D AFM system software (Asylum Research, Santa Barbara, CA), based in IGOR Pro (WaveMetrics, Lake Oswego, OR). A novel approach, based on computational algorithms for fractal analysis of surfaces applied for AFM data, was utilized to analyze the surface structure. The surfaces revealed a fractal structure at the nanometer scale. The fractal dimension, D, provided quantitative values that characterize the scale properties of surface geometry. Detailed characterization of the surface topography was obtained using statistical parameters, in accordance with ISO 25178-2: 2012. Results obtained by fractal analysis confirm the relationship between the value of the fractal dimension and the statistical surface roughness parameters. The surface structure of Bowman's membrane of the human cornea is complex. The analyzed AFM images confirm a fractal nature of the surface, which is not taken into account by classical surface statistical parameters. Surface fractal dimension could be useful in ophthalmology to quantify corneal architectural changes associated with different disease states to further our understanding of disease evolution.

  16. Ophthoselfie: Detailed Self-imaging of Cornea and Anterior Segment by Smartphone

    Directory of Open Access Journals (Sweden)

    Abdullah Kaya

    2017-06-01

    Full Text Available Objectives: To describe the ophthoselfie, a method by which everyone can take detailed self-images of the cornea and anterior segment with a smartphone. Materials and Methods: A 90-diopter non-contact double aspheric lens was attached to posterior camera of the smartphone by clear tape. Images of one eye on the screen of the smartphone could be seen with the other eye in the mirror and images were taken. Results: Accurate and detailed images of the cornea and anterior segment of the eye could be taken. Conclusion: The ophthoselfie allows everyone to take their own detailed anterior segment images by smartphone. To create a clear and detailed self-image of the cornea and anterior segment on the screen of a smartphone may lead to the development of new applications and facilitate patients’ early recognition of certain conditions like keratoconus, refractive errors, corneal rejection, and uveitis. This method may also be useful in some urgent situations by allowing patients to take self-images of the eye and share them with a physician.

  17. Ophthoselfie: Detailed Self-imaging of Cornea and Anterior Segment by Smartphone.

    Science.gov (United States)

    Kaya, Abdullah

    2017-06-01

    To describe the ophthoselfie, a method by which everyone can take detailed self-images of the cornea and anterior segment with a smartphone. A 90-diopter non-contact double aspheric lens was attached to posterior camera of the smartphone by clear tape. Images of one eye on the screen of the smartphone could be seen with the other eye in the mirror and images were taken. Accurate and detailed images of the cornea and anterior segment of the eye could be taken. The ophthoselfie allows everyone to take their own detailed anterior segment images by smartphone. To create a clear and detailed self-image of the cornea and anterior segment on the screen of a smartphone may lead to the development of new applications and facilitate patients' early recognition of certain conditions like keratoconus, refractive errors, corneal rejection, and uveitis. This method may also be useful in some urgent situations by allowing patients to take self-images of the eye and share them with a physician.

  18. Contribution of the cornea and internal surfaces to the change of ocular aberrations with age

    Science.gov (United States)

    Artal, Pablo; Berrio, Esther; Guirao, Antonio; Piers, Patricia

    2002-01-01

    We studied the age dependence of the relative contributions of the aberrations of the cornea and the internal ocular surfaces to the total aberrations of the eye. We measured the wave-front aberration of the eye with a Hartmann-Shack sensor and the aberrations of the anterior corneal surface from the elevation data provided by a corneal topography system. The aberrations of the internal surfaces were obtained by direct subtraction of the ocular and corneal wave-front data. Measurements were obtained for normal healthy subjects with ages ranging from 20 to 70 years. The magnitude of the RMS wave-front aberration (excluding defocus and astigmatism) of the eye increases more than threefold within the age range considered. However, the aberrations of the anterior corneal surface increase only slightly with age. In most of the younger subjects, total ocular aberrations are lower than corneal aberrations, while in the older subjects the reverse condition occurs. Astigmatism, coma, and spherical aberration of the cornea are larger than in the complete eye in younger subjects, whereas the contrary is true for the older subjects. The internal ocular surfaces compensate, at least in part, for the aberrations associated with the cornea in most younger subjects, but this compensation is not present in the older subjects. These results suggest that the degradation of the ocular optics with age can be explained largely by the loss of the balance between the aberrations of the corneal and the internal surfaces.

  19. Safety levels for exposure of cornea and lens to very high-frequency ultrasound.

    Science.gov (United States)

    Silverman, R H; Lizzi, F L; Ursea, B G; Cozzarelli, L; Ketterling, J A; Deng, C X; Folberg, R; Coleman, D J

    2001-09-01

    Very high-frequency (50-MHz) ultrasound is widely used for imaging the anterior segment of the eye. Our aim was to determine whether exposures to ultrasound at and above those used in diagnostic imaging systems might cause bioeffects in ocular tissues. We characterized the output parameters of a polyvinylidene difluoride transducer using a needle hydrophone. We exposed sites on the cornea or lens of rabbits for up to 30 minutes at a 10-kHz pulse repetition frequency. Tissue obtained immediately or 24 hours after exposure was examined by light microscopy. A numeric model was implemented to calculate expected temperature elevations in the cornea and lens under experimental conditions. No tissue changes were observed directly or by slit lamp. Light microscopy showed no abnormalities attributable to ultrasound exposure. Simulations showed that even long-term exposures should produce temperature elevations of less than 1 degree C in both the cornea and lens. With the use of exposure parameters 4 to 5 orders of magnitude greater than encountered in a clinical situation, no tissue changes were observed. This is consistent with the small (0.2 degrees C) temperature rises computed in simulations. The lack of biological effects is attributable to the small dimensions of the focal zone, allowing rapid dissipation of heat, and the low total acoustic power produced by the transducer.

  20. Early expression of surfactant proteins D in Fusarium solani infected rat cornea.

    Science.gov (United States)

    Che, Cheng-Ye; Li, Xiao-Jing; Jia, Wen-Yan; Li, Na; Xu, Qiang; Lin, Jing; Wang, Qing; Jiang, Nan; Hu, Li-Ting; Zhao, Gui-Qiu

    2012-01-01

    To investigate the early expression of surfactant proteins D(SP-D) in Fusarium solani infected rat cornea. Wistar rats were divided into group A, B and C randomly. The right eyes were chosen as the experiment one. Group A was control group. Group B was not inoculated with Fusarium solani. Group C was taken as fusarium solani keratitis model. Five rats in group B and C were executed randomly at 6, 12, 24, 48 and 96 hours respectively after the experimental model being established. The expression of SP-D was assessed through immunohistochemistry and reverse transcription polymerase chain reaction(RT-PCR). RT-PCR detected that the SP-D mRNA expression was low in the corneal of normal rats and group B. The expression of fungal infected cornea increased gradually and reached the peak at 24 hours in group C. The synchronous expression of group B and C were in significant difference (Pfusarium solani infected cornea. SP-D may play a role in the early innate immunity response of the corneal resistance to Fusarium solani infection.

  1. In vivo multiphoton imaging of the cornea: polarization-resolved second harmonic generation from stromal collagen

    Science.gov (United States)

    Latour, G.; Gusachenko, I.; Kowalczuk, L.; Lamarre, I.; Schanne-Klein, M.-C.

    2012-03-01

    Multiphoton microscopy provides specific and contrasted images of unstained collagenous tissues such as tendons or corneas. Polarization-resolved second harmonic generation (SHG) measurements have been implemented in a laserscanning multiphoton microscope. Distortion of the polarimetric response due to birefringence and diattenuation during propagation of the laser excitation has been shown in rat-tail tendons. A model has been developed to account for these effects and correct polarization-resolved SHG images in thick tissues. This new modality is then used in unstained human corneas to access two quantitative parameters: the fibrils orientation within the collagen lamellae and the ratio of the main second-order nonlinear tensorial components. Orientation maps obtained from polarization resolution of the trans-detected SHG images are in good agreement with the striated features observed in the raw images. Most importantly, polarization analysis of the epi-detected SHG images also enables to map the fibrils orientation within the collagen lamellae while epi-detected SHG images of corneal stroma are spatially homogenous and do not enable direct visualization of the fibrils orientation. Depth profiles of the polarimetric SHG response are also measured and compared to models accounting for orientation changes of the collagen lamellae within the focal volume. Finally, in vivo polarization-resolved SHG is performed in rat corneas and structural organization of corneal stroma is determined using epi-detected signals.

  2. Search, Effort, and Locus of Control

    OpenAIRE

    McGee, Andrew; McGee, Peter

    2011-01-01

    We test the hypothesis that locus of control – one's perception of control over events in life – influences search by affecting beliefs about the efficacy of search effort in a laboratory experiment. We find that reservation offers and effort are increasing in the belief that one's efforts influence outcomes when subjects exert effort without knowing how effort influences the generation of offers but are unrelated to locus of control beliefs when subjects are informed about the relationship b...

  3. 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....

  4. 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.

  5. Fragile X Syndrome

    OpenAIRE

    Wilmar Saldarriaga; Flora Tassone; Laura Yuriko González-Teshima; Jose Vicente Forero-Forero; Sebastián Ayala-Zapata; Randi Hagerman

    2015-01-01

    Fragile X Syndrome (FXS) is a genetic disease due to a CGG trinucleotide expansion, named full mutation (greater than 200 CGG repeats), in the fragile X mental retardation 1 gene locus Xq27.3; which leads to an hypermethylated region in the gene promoter therefore silencing it and lowering the expression levels of the fragile X mental retardation 1, a protein involved in synaptic plasticity and maturation.  Individuals with FXS present with intellectual disability, autism, hyperactivity, long...

  6. 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....

  7. Optics of the average normal cornea from general and canonical representations of its surface topography.

    Science.gov (United States)

    Navarro, Rafael; González, Luis; Hernández, José L

    2006-02-01

    Generally, the analysis of corneal topography involves fitting the raw data to a parametric geometric model that includes a regular basis surface, plus some sort of polynomial expansion to adjust the more irregular residual component. So far, these parametric models have been used in their canonical form, ignoring that the observation (keratometric) coordinate system is different from corneal axes of symmetry. Here we propose, instead, to use the canonical form when the topography is referenced to the intrinsic corneal system of coordinates, defined by its principal axes of symmetry. This idea is implemented using the general expression of an ellipsoid to fit the raw data given by the instrument. Then, the position and orientation of the three orthogonal semiaxes of the ellipsoid, which define the intrinsic Cartesian system of coordinates for normal corneas, can be identified by passing to the canonical form, by standard linear algebra. This model has been first validated experimentally obtaining significantly lower values for rms fitting error as compared with previous standard models: spherical, conical, and biconical. The fitting residual was then adjusted by a Zernike polynomial expansion. The topographies of 123 corneas were analyzed obtaining their radii of curvature, conic constants, Zernike coefficients, and the direction and position of the optical axis of the ellipsoid. The results were compared with those obtained using the standard models. The general ellipsoid model provides more negative values for the conic constants and lower apex radii (more prolate shapes) than the standard models applied to the same data. If the data are analyzed using standard models, the resulting mean shape of the cornea is consistent with previous studies, but when using the ellipsoid model we find new interesting features: The mean cornea is a more prolate ellipsoid (apical power 50 D), the direction of the optical axis is about 2.3 degrees nasal, and the residual term shows

  8. Optics of the average normal cornea from general and canonical representations of its surface topography

    Science.gov (United States)

    Navarro, Rafael; González, Luis; Hernández, José L.

    2006-02-01

    Generally, the analysis of corneal topography involves fitting the raw data to a parametric geometric model that includes a regular basis surface, plus some sort of polynomial expansion to adjust the more irregular residual component. So far, these parametric models have been used in their canonical form, ignoring that the observation (keratometric) coordinate system is different from corneal axes of symmetry. Here we propose, instead, to use the canonical form when the topography is referenced to the intrinsic corneal system of coordinates, defined by its principal axes of symmetry. This idea is implemented using the general expression of an ellipsoid to fit the raw data given by the instrument. Then, the position and orientation of the three orthogonal semiaxes of the ellipsoid, which define the intrinsic Cartesian system of coordinates for normal corneas, can be identified by passing to the canonical form, by standard linear algebra. This model has been first validated experimentally obtaining significantly lower values for rms fitting error as compared with previous standard models: spherical, conical, and biconical. The fitting residual was then adjusted by a Zernike polynomial expansion. The topographies of 123 corneas were analyzed obtaining their radii of curvature, conic constants, Zernike coefficients, and the direction and position of the optical axis of the ellipsoid. The results were compared with those obtained using the standard models. The general ellipsoid model provides more negative values for the conic constants and lower apex radii (more prolate shapes) than the standard models applied to the same data. If the data are analyzed using standard models, the resulting mean shape of the cornea is consistent with previous studies, but when using the ellipsoid model we find new interesting features: The mean cornea is a more prolate ellipsoid (apical power 50 D), the direction of the optical axis is about 2.3° nasal, and the residual term shows three

  9. Correlation of Biomicroscopic Findings with Confocal Microscopy in Eyes with Amiodarone-Induced Cornea Verticillata

    Directory of Open Access Journals (Sweden)

    Emine Kaya

    2014-01-01

    Full Text Available Objectives: To investigate the correlation between biomicroscopic and confocal microscopic findings in eyes with amiodarone-induced cornea verticillata. Materials and Methods: Sixteen eyes of 8 patients with amiodarone-induced cornea verticillata were evaluated. Eyes with keratopathy were staged according to Orlando slit-lamp microscopy classification. Confocal laser-scanning microscopy was performed by Rostock cornea modulated to HRT II (Heidelberg Engineering GmbH, Heidelberg, Germany, and staging was done according to Falke’s classification that is based on the degree of epithelial basal cell deposit accumulation. The relation between biomicroscopic staging and corneal involvement detected on confocal microscopy was assessed by Spearman correlation analysis. Results: The mean age of the 8 patients (5 male, 3 female was 63.1±7.2 (50 to 69 years. The mean duration of drug treatment was 12.1±11.8 (3 to 36 months, and the mean drug treatment dose was 312.5±223.2 (100 to 800 mg/day. At the time of examination, 50% of the patients had already given up the treatment at a mean of 29.5±15.8 (6 to 40 months ago, whereas the other 50% were still on amiodarone therapy. Hyper-reflecting deposits were observed in the basal epithelium, anterior-, mid-and deep-stroma, and in the endothelium on confocal microscopic examination. Correlation was detected between biomicroscopic and confocal microscopic stages (r=0.770, p<0.001. Frequency of detecting deposits in the stroma and endothelium was found to be increasing as the biomicroscopic stage increased (r=0.844; p<0.001 and r=0.551; p<0.01, respectively. Conclusion: In amiodarone-induced cornea verticillata, correlated results were detected between biomicroscopic and confocal microscopic staging. Therefore, in clinics where confocal microscopy is not available, biomicroscopic staging can be used as a guiding parameter in eyes with amiodarone-induced cornea verticillata. (Turk J Ophthalmol 2014; 44: 63-67

  10. Chronic Lunar Dust Exposure on Rat Cornea: Evaluation by Gene Expression Profiling

    Science.gov (United States)

    Theriot, C. A.; Glass, A.; Lam, C-W.; James, J.; Zanello, S. B.

    2014-01-01

    Lunar dust is capable of entering habitats and vehicle compartments by sticking to spacesuits or other objects that are transferred into the spacecraft from the lunar surface and has been reported to cause irritation upon exposure. During the Apollo missions, crewmembers reported irritation specifically to the skin and eyes after contamination of the lunar and service modules. It has since been hypothesized that ocular irritation and abrasion might occur as a result of such exposure, impairing crew vision. Recent work has shown that both ultrafine and unground lunar dust exhibited minimal irritancy of the ocular surface (i.e., cornea); however, the assessment of the severity of ocular damage resulting from contact of lunar dust particles to the cornea has focused only on macroscopic signs of mechanical irritancy and cytotoxicity. Given the chemical reactive properties of lunar dust, exposure of the cornea may contribute to detrimental effects at the molecular level including but not limited to oxidative damage. Additionally, low level chronic exposures may confound any results obtained in previous acute studies. We report here preliminary results from a tissue sharing effort using 10-week-old Fischer 344 male rats chronically exposed to filtered air or jet milled lunar dust collected during Apollo 14 using a Jaeger-NYU nose-only chamber for a total of 120 hours (6 hours daily, 5 days a week) over a 4-week period. RNA was isolated from corneas collected from rats at 1 day and 7 days after being exposed to concentrations of 0, 20, and 60 mg/m3 of lunar dust. Microarray analysis was performed using the Affymetrix GeneChip Rat Genome 230 2.0 Array with Affymetrix Expression Console and Transcriptome Analysis Console used for normalization and secondary analysis. An Ingenuity iReport"TM" was then generated for canonical pathway identification. The number of differentially expressed genes identified increases with dose compared to controls suggesting a more severe

  11. Locus coeruleus syndrome as a complication of tectal surgery

    NARCIS (Netherlands)

    Kronenburg, Annick; Spliet, Wim G.; Broekman, Marike; Robe, Pierre

    2015-01-01

    We describe a case of a 48-year-old woman who underwent a resection of a tectal pilocytic astrocytoma complicated by a sequence of fluctuating consciousness, psychosis with complex hallucinations and lasting sleeping disturbances in which she vividly acts out her dreams. Based on the clinical and an

  12. Locus heterogeneity in autosomal dominant spinocerebellar ataxia: Evidence for the existence of a fifth locus

    Energy Technology Data Exchange (ETDEWEB)

    Sarrazin, J.; Rouleau, G.A. [Montreal General Hospital, Quebec (Canada); Andermann, E. [Montreal Neurological Institute and Hospital, Quebec (Canada)] [and others

    1994-09-01

    The autosomal dominantly inherited spinocerebellar ataxias (SCAs) are a heterogeneous group of neurodegenerative disorders. To date, four loci have been identified: the SCA-1 locus (on chromosome (chr) 6p), the SCA-2 locus (on chr 12q), the SCA-3/MJD locus (on chr 14q), and more recently an SCA-4 locus was described (chr 16q) in a Utah kindred. We have studied one large French Canadian kindred with four generations of living affected individuals segregating an autosomal dominant form of SCA. Linkage analysis using anonymous DNA markers which flank the four previously described loci significantly excludes the French Canadian kindred from the SCA-1, SCA-2, SCA-3/MJD and SCA-4 loci. Therefore a fifth, still unmapped, SCA locus remains to be identified.

  13. Validation of an endothelial roll preparation for Descemet Membrane Endothelial Keratoplasty by a cornea bank using "no touch" dissection technique.

    Science.gov (United States)

    Marty, Anne-Sophie; Burillon, Carole; Desanlis, Adeline; Damour, Odile; Kocaba, Viridiana; Auxenfans, Céline

    2016-06-01

    Descemet Membrane Endothelial Keratoplasty (DMEK) selectively replaces the damaged posterior part of the cornea. However, the DMEK technique relies on a manually-performed dissection that is time-consuming, requires training and presents a potential risk of endothelial graft damages leading to surgery postponement when performed by surgeons in the operative room. To validate precut corneal tissue preparation for DMEK provided by a cornea bank in order to supply a quality and security precut endothelial tissue. The protocol was a technology transfer from the Netherlands Institute for Innovative Ocular Surgery (NIIOS) to Lyon Cornea Bank, after formation in NIIOS to the DMEK "no touch" dissection technique. The technique has been validated in selected conditions (materials, microscope) and after a learning curve, cornea bank technicians prepared endothelial tissue for DMEK. Endothelial cells densities (ECD) were evaluated before and after preparation, after storage and transport to the surgery room. Microbiological and histological controls have been done. Twenty corneas were manually dissected; 18 without tears. Nineteen endothelial grafts formed a double roll. The ECD loss after cutting was 3.3 % (n = 19). After transportation 7 days later, we found an ECD loss of 25 % (n = 12). Three days after cutting and transportation, we found 2.1 % of ECD loss (n = 7). Histology found an endothelial cells monolayer lying on Descemet membrane. The mean thickness was 12 ± 2.2 µm (n = 4). No microbial contamination was found (n = 19). Endothelial roll stability has been validated at 3 days in our cornea bank. Cornea bank technicians trained can deliver to surgeons an ECD controlled, safety and ready to use endothelial tissue, for DMEK by "no touch" technique, allowing time saving, quality and security for surgeons.

  14. In vitro permeation characteristics of moxifloxacin from oil drops through excised goat, sheep, buffalo and rabbit corneas.

    Science.gov (United States)

    Pawar, P K; Majumdar, D K

    2007-11-01

    The objective of present investigation was to study the in vitro permeation characteristics of moxifloxacin from oil drops through freshly excised goat, sheep, buffalo and rabbit corneas. Moxifloxacin, 0.043 to 0.048% (w/v) ophthalmic solutions with or without (0.5% v/v) benzyl alcohol were made in arachis, castor, cottonseed, olive, soybean, sunflower and sesame oils. Permeation studies were conducted by putting 1 ml oil formulation on cornea (0.50 cm2) fixed between donor and receptor compartments of an all glass modified Franz diffusion cell and measuring the drug permeated in receptor (containing 10 ml bicarbonate ringer, pH 7.4 at 37 degrees C under stirring) by spectrophotometry at 291 nm, after 120 min. Post permeation corneal hydration was measured to assess corneal damage. The study was designed with paired corneas i.e. one cornea of an animal received formulation without benzyl alcohol while the contralateral cornea received formulation with benzyl alcohol. Moxifloxacin ophthalmic solution in castor oil showed maximum permeation with all the corneas. Addition of benzyl alcohol, a preservative, to oil drops reduced permeation of moxifloxacin from each oil drop, with corneas of all the species. Partition experiments with moxifloxacin oil drops and phosphate buffer (pH 7.4) indicated higher partitioning of drug in the oil phase, in presence of benzyl alcohol. Thus results of permeation are consistent with the partition characteristics of drug between oil and aqueous phase. Corneal hydration obtained with all the formulations was between 75 to 80% indicating no corneal damage.

  15. Molecular diagnosis of Down ' s syndrome

    Institute of Scientific and Technical Information of China (English)

    王树玉; 贾婵维; 任国庆; 马延敏; 吕巍; 丁锋; 韩健

    2003-01-01

    Objective To establish a new diagnostic method for Down ' s syndrome using polymerase chain reaction (PCR).Methods DNA extracted from five healthy individuals and five Down ' s syndrome patients was amplified in six specific tetranucleotide repeat loci on chromosome 21 using PCR. An accurate diagnosis was made by analyzing allelic distribution at each locus. Results All Down ' s syndrome patients were identified as having at least two loci with three alleles, while none of the healthy individuals had three alleles. In addition, when two alleles were identified for a particular locus in the Down ' s syndrome samples, it was more likely that the intensity ratio between the two alleles was close to 2∶ 1.Conclusion The molecular method can provide a fast, accurate, and economical alternation for the traditional cytogenetic diagnostic method for Down ' s syndrome.

  16. 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.

  17. Localization and expression of CHST6 and keratan sulfate proteoglycans in the human cornea.

    Science.gov (United States)

    Di Iorio, Enzo; Barbaro, Vanessa; Volpi, Nicola; Bertolin, Marina; Ferrari, Barbara; Fasolo, Adriano; Arnaldi, Renato; Brusini, Paolo; Prosdocimo, Giovanni; Ponzin, Diego; Ferrari, Stefano

    2010-08-01

    Macular corneal dystrophy (MCD; OMIM 217800) is a rare autosomal recessive inherited disorder caused by mutations in the carbohydrate sulfotransferase 6 (CHST6) and characterised by the presence of unsulfated keratan sulfate proteoglycans (KSPGs) forming abnormal deposits that eventually lead to visual impairment. The aim of this study is to understand in which corneal cells CHST6 and KSPGs are expressed and exert their activity. Expression and localization of CHST6, keratan sulfate (KS) and proteins of the KSPGs, such as mimecan and lumican, were assessed both in human cornea sections and in cultured primary keratinocytes (n = 3) and keratocytes (n = 4). Immunohistochemistry, semiquantitative RT-PCR, in situ RNA hybridization and HPLC analysis of glycosaminoglycans were used as read-outs. In human corneas KS was predominantly found in the stroma, but absent, or barely detectable, in the corneal epithelium. A similar pattern of distribution was found in the epidermis, with KS mainly localised in the derma. As expected, in the cornea CHST6 (the gene encoding the enzyme which transfers sulfate residues onto KSPGs) was found expressed in the suprabasal, but not basal, layers of the epithelium, in the stroma and in the endothelium. Analyses of KS by means of HPLC showed that in vitro cultured stromal keratocytes express and secrete more KS than keratinocytes, thus mirroring results observed in vivo. Similarly expression of the CHST6 gene and of KS proteoglycans such as mimecan, lumican is limited to stromal keratocytes. Unlike keratocytes, corneal keratinocytes do not synthesize mimecan or lumican, and express very little, if none, CHST6. Any drug/gene therapy or surgical intervention aimed at curing this rare genetic disorder must therefore involve and target stromal keratocytes. If coupled to the accuracy of HPLC-based assay that we developed to determine the amount of KS in serum, our findings could lead to more targeted therapeutic treatments of the ocular features

  18. Biocompatibility of poly(ethylene glycol) and poly(acrylic acid) interpenetrating network hydrogel by intrastromal implantation in rabbit cornea.

    Science.gov (United States)

    Zheng, Luo Luo; Vanchinathan, Vijay; Dalal, Roopa; Noolandi, Jaan; Waters, Dale J; Hartmann, Laura; Cochran, Jennifer R; Frank, Curtis W; Yu, Charles Q; Ta, Christopher N

    2015-10-01

    We evaluated the biocompatibility of a poly(ethylene glycol) and poly(acrylic acid) (PEG/PAA) interpenetrating network hydrogel designed for artificial cornea in a rabbit model. PEG/PAA hydrogel measuring 6 mm in diameter was implanted in the corneal stroma of twelve rabbits. Stromal flaps were created with a microkeratome. Randomly, six rabbits were assigned to bear the implant for 2 months, two rabbits for 6 months, two rabbits for 9 months, one rabbit for 12 months, and one rabbit for 16 months. Rabbits were evaluated monthly. After the assigned period, eyes were enucleated, and corneas were processed for histology and immunohistochemistry. There were clear corneas in three of six rabbits that had implantation of hydrogel for 2 months. In the six rabbits with implant for 6 months or longer, the corneas remained clear in four. There was a high rate of epithelial defect and corneal thinning in these six rabbits. One planned 9-month rabbit developed extrusion of implant at 4 months. The cornea remained clear in the 16-month rabbit but histology revealed epithelial in-growth. Intrastromal implantation of PEG/PAA resulted in a high rate of long-term complications.

  19. Ethical Considerations on Heterogeneous Cornea Transplant%异种角膜移植的伦理考量

    Institute of Scientific and Technical Information of China (English)

    张燕

    2011-01-01

    由于移植技术的进步以及异种角膜移植技术自身的优势,异种角膜移植有望成为眼科临床常规诊疗手段之一,为缓解同种角膜移植供体短缺的压力提供可能.分析了异种角膜移植的可行性,并就异种角膜移植涉及的部分伦理问题、安全性问题;人的同一性及完整性问题;患者接受度问题;角膜供体资源管理和分配问题;动物保护问题进行了探讨.%According to advanced transplantation technology and the advantages of comeal stroma, heterogeneous cornea transplant is expected to become one of the conventional means of ophthalmology clinical treatment,and it provides the possibility for easing the shortage of the same cornea transplant donation. This paper analyzed the feasibility of heterogeneous cornea transplant and discussed some ethical issues about heterogeneous cornea transplant: safety issue, people in the identity and integrity problems, degree about patients received, heterogeneous donor cornea resources management and distribution issue and animal protection issue.

  20. 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

    Background: Cornea plana (CNA) is a hereditary congenital abnormality of the cornea characterized by reduced corneal curvature, extreme hypermetropia, corneal clouding and hazy corneal limbus. The recessive form, CNA2, is associated with homozygous or compound heterozygous mutations of the kerato......Background: Cornea plana (CNA) is a hereditary congenital abnormality of the cornea characterized by reduced corneal curvature, extreme hypermetropia, corneal clouding and hazy corneal limbus. The recessive form, CNA2, is associated with homozygous or compound heterozygous mutations...... 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...... 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...

  1. 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.

  2. [Difficult cornea procurement: causes and consequences of the exceptional situation in France].

    Science.gov (United States)

    Delbosc, B

    2000-02-01

    Despite scientific advances, corneal grafting is still in a crucial situation in France in 1999. Over the last 3 years, the number of corneal grafts (2 903 in 1996, 3 213 in 1997, and 4 053 in 1998) has been insufficient to satisfy estimated needs (8 041 in 1996, 8 303 in 1997, 7 400 in 1998). The consequences are waiting lists, long time on waiting lists, and regional differences. This situation results more from difficulties in the cornea procurement system than from limited numbers of potential donors or restricted selection criteria. Progress will depend greatly on structural changes.

  3. 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

  4. The Riley-Day syndrome. Familial dysautonomy, central autonomic dysfunction.

    Science.gov (United States)

    François, J

    1977-01-01

    The Riley-Day syndrome is characterized by a dysfunction of the autonomous nervous system, sensory disturbances, neurological disorders, psychical anomalies and important ophthalmological symptoms, such as absence of tears, corneal anaesthesia, keratinized conjunctiva and cornea; myosis after instillation of methacholine. The diagnosis is based on the absence of fungiform papillae of the tongue and the absence of reaction after intradermic injection of histamine. The inheritance is autosomal recessive. The disease results probably from an enzymatic insufficiency.

  5. 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.

  6. A suppressor locus for MODY3-diabetes

    Science.gov (United States)

    Garcia-Gonzalez, Miguel A.; Carette, Claire; Bagattin, Alessia; Chiral, Magali; Makinistoglu, Munevver Parla; Garbay, Serge; Prévost, Géraldine; Madaras, Cécile; Hérault, Yann; Leibovici, Michel; Pontoglio, Marco

    2016-01-01

    Maturity Onset Diabetes of the Young type 3 (MODY3), linked to mutations in the transcription factor HNF1A, is the most prevalent form of monogenic diabetes mellitus. HNF1alpha-deficiency leads to defective insulin secretion via a molecular mechanism that is still not completely understood. Moreover, in MODY3 patients the severity of insulin secretion can be extremely variable even in the same kindred, indicating that modifier genes may control the onset of the disease. With the use of a mouse model for HNF1alpha-deficiency, we show here that specific genetic backgrounds (C3H and CBA) carry a powerful genetic suppressor of diabetes. A genome scan analysis led to the identification of a major suppressor locus on chromosome 3 (Moda1). Moda1 locus contains 11 genes with non-synonymous SNPs that significantly interacts with other loci on chromosomes 4, 11 and 18. Mechanistically, the absence of HNF1alpha in diabetic-prone (sensitive) strains leads to postnatal defective islets growth that is remarkably restored in resistant strains. Our findings are relevant to human genetics since Moda1 is syntenic with a human locus identified by genome wide association studies of fasting glycemia in patients. Most importantly, our results show that a single genetic locus can completely suppress diabetes in Hnf1a-deficiency. PMID:27667715

  7. Locus of Equity and Brand Extension

    NARCIS (Netherlands)

    S.M.J. van Osselaer (Stijn); J.W. Alba (Joseph)

    2003-01-01

    textabstractPrevailing wisdom assumes that brand equity increases when a brand touts its desirable attributes. We report conditions under which the use of attribute information to promote a product can shift the locus of equity from brand to attribute, thereby reducing the attractiveness of extensio

  8. Locus of Equity and Brand Extension

    NARCIS (Netherlands)

    S.M.J. van Osselaer (Stijn); J.W. Alba (Joseph)

    2003-01-01

    textabstractPrevailing wisdom assumes that brand equity increases when a brand touts its desirable attributes. We report conditions under which the use of attribute information to promote a product can shift the locus of equity from brand to attribute, thereby reducing the attractiveness of extensio

  9. Two-photon autofluorescence lifetime and SHG imaging of healthy and diseased human corneas

    Science.gov (United States)

    Batista, Ana; Breunig, Hans Georg; Uchugonova, Aisada; Seitz, Berthold; Morgado, António Miguel; König, Karsten

    2015-03-01

    Corneal function can be drastically affected by several degenerations and dystrophies, leading to blindness. Early diagnosis of corneal disease is of major importance and it may be accomplished by monitoring changes of the metabolic state and structural organization, the first detectable pathological signs, by two-photon excitation autofluorescence lifetime and second-harmonic generation imaging. In this study, we propose to use these imaging techniques to differentiate between healthy and pathological corneas. Images were acquired using a laser-scanning microscope with a broadband sub-15 femtosecond near-infrared pulsed laser and a 16-channel photomultiplier tube detector for signal collection. This setup allows the simultaneous excitation of metabolic co-factors and to identify them based on their fluorescence spectra. We were able to discriminate between healthy and pathological corneas using two-photon excitation autofluorescence lifetime and second-harmonic generation imaging from corneal epithelium and stroma. Furthermore, differences between different pathologies were observed. Alterations in the metabolic state of corneal epithelial cells were observed using the autofluorescence lifetime of the metabolic co-factors. In the corneal stroma, we observed not only alterations in the collagen fibril structural organization but also alterations in the autofluorescence lifetime. Further tests are required as the number of pathological samples must be increased. In the future, we intend to establish a correlation between the metabolic and structural changes and the disease stage. This can be a step forward in achieving early diagnosis.

  10. 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.

  11. Control of scar tissue formation in the cornea: strategies in clinical and corneal tissue engineering.

    Science.gov (United States)

    Wilson, Samantha L; El Haj, Alicia J; Yang, Ying

    2012-09-18

    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.

  12. Evaluating the material parameters of the human cornea in a numerical model.

    Science.gov (United States)

    Sródka, Wiesław

    2011-01-01

    The values of the biomechanical human eyeball model parameters reported in the literature are still being disputed. The primary motivation behind this work was to predict the material parameters of the cornea through numerical simulations and to assess the applicability of the ubiquitously accepted law of applanation tonometry - the Imbert-Fick equation. Numerical simulations of a few states of eyeball loading were run to determine the stroma material parameters. In the computations, the elasticity moduli of the material were related to the stress sign, instead of the orientation in space. Stroma elasticity secant modulus E was predicted to be close to 0.3 MPa. The numerically simulated applanation tonometer readings for the cornea with the calibration dimensions were found to be lower by 11 mmHg then IOP = 48 mmHg. This discrepancy is the result of a strictly mechanical phenomenon taking place in the tensioned and simultaneously flattened corneal shell and is not related to the tonometer measuring accuracy. The observed deviation has not been amenable to any GAT corrections, contradicting the Imbert-Fick law. This means a new approach to the calculation of corrections for GAT readings is needed.

  13. Cornea Collagen Cross-linking for Keratoconus: A Comparison between Accelerated and Conventional Methods

    Science.gov (United States)

    Razmjoo, Hasan; Peyman, Alireza; Rahimi, Ali; Modrek, Hoda Jafari

    2017-01-01

    Background: Keratoconus is a progressive degenerative disorder of the cornea in which structural changes in the cornea cause it to become thin and conical in shape. Recently, collagen cross-linking (CXL) has been introduced as an effective intervention in management of progressive keratoconus. Accelerated CXL is a new protocol of this procedure which reduces corneal ultraviolet irradiation exposure time to 5 min. This study aimed to compare visual acuity, keratometry and topographic criteria of keratoconic eyes after conventional and accelerated CXL with a six-month follow-up. Materials and Methods: In this prospective interventional study we assessed eyes of 40 patients. Patients were divided into two groups randomly. One group underwent accelerated (5 min) CXL and the other underwent conventional (30 min) CXL. Visual acuity, topographic criteria and keratometry were assessed preoperatively and 6 months postoperatively. Results: In the present study we assessed 40 patients, 50% of which were right eye (OD) and 50% were left eye (OS). Mean age of patients in the accelerated group was 22.10 and in the conventional group was 22.80 years. Our results showed no significant differences between visual acuity, keratometric and topographic criteria in the two groups before intervention. Likewise our results manifested no significant difference between visual acuity, keratometric, refractive and topographic criteria after intervention. Conclusion: According to our survey topographic criteria and keratometry improvement in the accelerated and conventional protocol are the same. So accelerated protocol is suggested as a safe and effective option for management of progressive keratoconus. PMID:28299302

  14. Animal study on expression of laminin and fibronectin in cornea during wound healing following alkali burn

    Institute of Scientific and Technical Information of China (English)

    赵桂秋; 马轶群; 梁涛; 姜涛; 王传富; 张妍霞

    2003-01-01

    Objective: To observe the expression of laminin and fibronectin in alkali-burned corneas in rats.Methods: A total of 18 normal Wistar rats were randomly divided into 6 groups (n=3 in each group). For each rat, one eye was injured by alkali burn, the other one was taken as the normal control. Then all the corneas were surgically removed and the expression of laminin and fibronectin was observed with immunohistochemistry respectively at 7 hours, 1 day, 3 days, 7 days, 14 days and 28 days after alkali burn. Results: Compared with that of the normal controls, the expression of laminin and fibronectin of the burned eyes was dramatically higher at 7 hours, reached peak at 14 days and decreased to the normal level at 28 days after alkali burn. Conclusions: In the process of wound healing after alkali burn, the expression of laminin and fibronectin increases dramatically, which suggests that laminin and fibronectin may participate in the process of corneal wound healing.

  15. Pre- and postoperative optical resolution of the cornea: a preliminary report

    Science.gov (United States)

    Parel, Jean-Marie A.; Simon, Gabriel; Rol, Pascal O.; Ren, Qiushi; Lee, William E.

    1993-06-01

    The effect of novel refractive surgical techniques on visual acuity and contrast sensitivity is normally determined by the outcome of human clinical trials. For example, ArF laser photorefractive keratoplasty follows an algorithm based on the patient's preoperative data for keratometry, refraction, pachometry, and ocular length all measured with ultrasound. A normalized ablation rate (which is function of the laser fluence), and the desired refractive correction are then used to calculate the ablation depth. On the day of surgery, the epithelium is mechanically removed and the bare cornea photoablated. Finally, the cornea may be medicated with a topical application of antibiotics and the eye is patched. On postoperative day 7, the epithelium is healed and visual acuity and keratometry are measured. With PRK, the theoretical outcome refraction should be within +/- 0.25 D. Thus far however, reproducibility is only of +/- 2 D. We believe the large discrepancy between theory and practice is due to several parameters that vary patient-to-patient.

  16. Chromosome mutations and tissue regeneration in the cornea after the UV laser irradiation

    Science.gov (United States)

    Razhev, Alexander M.; Bagayev, Sergei N.; Lebedeva, Lidya I.; Akhmametyeva, Elena M.; Zhupikov, Andrey A.

    2003-06-01

    In present paper the findings on chromosome mutations, the nature of damage and the repair of the cornea tissue after UV irradiation by excimer lasers at 193, 223 and 248 nm were made. Structural mutations induced by short-pulses UV irradiation were shown to be similar to spontaneous ones by the type, time of formation in the mitotic cycle and location of acentrics. Ten hours after irradiation of the cornea with doses of 0,09 to 1,5 J/cm2 the incidence of cells with chromosome aberrations increased linearly with dose and amounted to 11,7% at 248 nm, 5,5% at 223 nm and 2,6% at 193 nm per 1 J/cm2. No induced chromosome aberrations occurred 72 hour following irradiation. Within the dose range from 3,0 to 18 J/cm2 the cytogenesis effect of radiation was less manifest than that with the doses mentioned above, the frequency of chromosome aberrations being independent of either radiation wavelength or radiation dose and amounted of 2,5 to 3,0%. Thus, large doses of powerful short-pulse UV radiation are safe according to the structural mutation criterion.

  17. Geometrical custom modeling of human cornea in vivo and its use for the diagnosis of corneal ectasia.

    Directory of Open Access Journals (Sweden)

    Francisco Cavas-Martínez

    Full Text Available AIM: To establish a new procedure for 3D geometric reconstruction of the human cornea to obtain a solid model that represents a personalized and in vivo morphology of both the anterior and posterior corneal surfaces. This model is later analyzed to obtain geometric variables enabling the characterization of the corneal geometry and establishing a new clinical diagnostic criterion in order to distinguish between healthy corneas and corneas with keratoconus. METHOD: The method for the geometric reconstruction of the cornea consists of the following steps: capture and preprocessing of the spatial point clouds provided by the Sirius topographer that represent both anterior and posterior corneal surfaces, reconstruction of the corneal geometric surfaces and generation of the solid model. Later, geometric variables are extracted from the model obtained and statistically analyzed to detect deformations of the cornea. RESULTS: The variables that achieved the best results in the diagnosis of keratoconus were anterior corneal surface area (ROC area: 0.847, p<0.000, std. error: 0.038, 95% CI: 0.777 to 0.925, posterior corneal surface area (ROC area: 0.807, p<0.000, std. error: 0.042, 95% CI: 0,726 to 0,889, anterior apex deviation (ROC area: 0.735, p<0.000, std. error: 0.053, 95% CI: 0.630 to 0.840 and posterior apex deviation (ROC area: 0.891, p<0.000, std. error: 0.039, 95% CI: 0.8146 to 0.9672. CONCLUSION: Geometric modeling enables accurate characterization of the human cornea. Also, from a clinical point of view, the procedure described has established a new approach for the study of eye-related diseases.

  18. Assessing the viscoelasticity of green light induced CXL in the rabbit cornea by noncontact OCE and FEM

    Science.gov (United States)

    Han, Zhaolong; Li, Jiasong; Singh, Manmohan; Vantipalli, Srilatha; Aglyamov, Salavat R.; Wu, Chen; Liu, Chih-hao; Twa, Michael D.; Larin, Kirill V.

    2016-03-01

    The biomechanical properties of the cornea have a profound influence on its health and function. Rose bengal/green light corneal collagen cross-linking (RGX) has been proposed as an alternative to UV-A Riboflavin collagen cross-linking (UV-CXL) for treatment of keratoconus. However, the effects of RGX on the biomechanical properties of the cornea are not as well understood as UV-CXL. In this work, we demonstrate the feasibility of quantifying the viscoelasticity of the rabbit cornea before and after RGX using a noncontact method of phase-stabilized swept source optical coherence elastography (PhS-SSOCE) and finite element modeling (FEM). Viscoelastic FE models of the corneas were constructed to simulate the elastic wave propagation based on the OCE measurements. In addition, the effect of the fluid-structure interface (FSI) between the corneal posterior surface and aqueous humor on the elastic wave group velocity was also investigated. The effect of the FSI was first validated by OCE measurements and FEM simulations on contact lenses, and the OCE and FEM results were in good agreement. The Young's modulus of the rabbit cornea before RGX was assessed as E=80 kPa, and the shear viscosity was η=0.40 Pa•s at an intraocular pressure (IOP) of 15 mmHg. After RGX, the Young's modulus increased to E=112 kPa and shear viscosity decreased to η=0.37 Pa•s. Both the corneal OCE experiments and the FE simulations also demonstrated that the FSI significantly reduced the group velocity of the elastic wave, and thus, the FSI should be considered when determining the biomechanical properties of the cornea.

  19. Morphologic and histopathologic changes in the rabbit cornea produced by femtosecond laser-assisted multilayer intrastromal ablation.

    Science.gov (United States)

    Zhang, Zhen-Yong; Chu, Ren-Yuan; Zhou, Xing-Tao; Dai, Jin-Hui; Sun, Xing-Huai; Hoffman, Matthew R; Zhang, Xing-Ru

    2009-05-01

    To observe morphologic and histopathologic changes in the midperiphery of the rabbit cornea produced by femtosecond laser-assisted multilayer intrastromal ablation, determine whether this method may be used to correct myopia, and study how the cornea heals when the epithelium is not injured. The right eyes of 10 New Zealand White rabbits were used for the experiments. A 60-kHz femtosecond laser delivery system was used, and three lamellar layers of laser pulses were focused starting at a corneal depth of 180 microm and ending at 90 microm from the surface, with each successive layer placed 45 microm anterior to the previous layer. In the interface of the applanation contact lens cone, a 6-mm diameter aluminum circle was placed at the center to block the laser, and ablation was limited to the midperiphery of the cornea. The laser settings were spot/line separation, 10 microm; diameter, 8.5 mm; energy for ablating the stroma, 1.3 microJ. Topography examination was used to document changes in corneal power. Light microscopy, transmission electron microscopy (TEM), and confocal microscopy in vivo were applied to observe changes in the cornea. There was significant change in mean corneal power between baseline and postoperative month 3 (n = 8; P = 0.0001), with a decrease from 46.82 D to 44.42 D. There was no haze formation or refractive regression throughout the follow-up. There were no corneal structural abnormalities under light microscopy. Activated keratocytes and necrotic debris were visible under confocal microscopy. Fibroblasts were observed, and no myofibroblasts appeared under TEM. Multilayer intrastromal ablation by the femtosecond laser with intact epithelium in the midperiphery of the corneal stroma can flatten the cornea without causing haze formation or refractive regression. This procedure allows the cornea to heal differently than when traditional corneal refractive surgery is performed and the epithelium is damaged.

  20. Role of CTCF protein in regulating FMR1 locus transcription.

    Directory of Open Access Journals (Sweden)

    Stella Lanni

    Full Text Available Fragile X syndrome (FXS, the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation. An antisense transcript (FMR1-AS1, starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM alleles present the same boundary described in wild type (WT alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.

  1. EFFECT OF DONOR CORNEA PRESERVATION IN TISSUE-CULTURE AND IN MCCAREY-KAUFMANN MEDIUM ON CORNEAL GRAFT-REJECTION AND VISUAL-ACUITY

    NARCIS (Netherlands)

    MOLL, AC; VANRIJ, G; BEEKHUIS, WH; DELAVALETTE, JHCR; HERMANS, J; PELS, E; RINKELVANDRIEL, E

    1991-01-01

    In a retrospective study the rate of rejection and clouding of the donor cornea for other reasons was investigated in 230 penetrating keratoplasties performed between 1984-1986. Donor corneas were stored in McCarey-Kaufmann Medium (MK) at 4-degrees-C or in a modified Minimal Essential Medium (MEM)

  2. Isolation and characterization of soluble sulfated polysaccharide from the red seaweed Glucaric cornea; Isolamento e caracterizacao do polissacarideo sulfatado soluvel extraido da alga vermelha Gracilaria cornea

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Marcia R.S.; Freitas, Ana L.P. [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Bioquimica e Biologia Molecular]. E-mail: rubiamelo@yahoo.com; Feitosa, Judith P.A.; Paula, Regina C.M. de [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica]. E-mail: judith@dqoi.ufc.br

    2001-07-01

    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 {sup 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{sub pk} 7.4 x 10{sup 4} and 1.8 x 10{sup 4} g/mol and a minor fraction of M{sub pk} 2.1 x 10{sup 6} g/mol. (author)

  3. 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…

  4. WRN mutations in Werner syndrome patients: genomic rearrangements, unusual intronic mutations and ethnic-specific alterations.

    NARCIS (Netherlands)

    Friedrich, K.; Lee, L.; Leistritz, D.F.; Nurnberg, G.; Saha, B.; Hisama, F.M.; Eyman, D.K.; Lessel, D.; Nurnberg, P.; Li, C.; Garcia-F-Villalta, M.J.; Kets, C.M.; Schmidtke, J.; Cruz, V.T.; Akker, P.C. van den; Boak, J.; Peter, D.; Compoginis, G.; Cefle, K.; Ozturk, S.; Lopez, N.; Wessel, T. van; Poot, M.; Ippel, P.F.; Groff-Kellermann, B.; Hoehn, H.; Martin, G.M.; Kubisch, C.; Oshima, J.

    2010-01-01

    Werner syndrome (WS) is an autosomal recessive segmental progeroid syndrome caused by null mutations at the WRN locus, which codes for a member of the RecQ family of DNA helicases. Since 1988, the International Registry of Werner syndrome had enrolled 130 molecularly confirmed WS cases from among 11

  5. WRN mutations in Werner syndrome patients : genomic rearrangements, unusual intronic mutations and ethnic-specific alterations

    NARCIS (Netherlands)

    Friedrich, Katrin; Lee, Lin; Leistritz, Dru F.; Nuernberg, Gudrun; Saha, Bidisha; Hisama, Fuki M.; Eyman, Daniel K.; Lessel, Davor; Nuernberg, Peter; Li, Chumei; Garcia-F-Villalta, Maria J.; Kets, Carolien M.; Schmidtke, Joerg; Cruz, Vitor Tedim; Van den Akker, Peter C.; Boak, Joseph; Peter, Dincy; Compoginis, Goli; Cefle, Kivanc; Ozturk, Sukru; Lopez, Norberto; Wessel, Theda; Poot, Martin; Ippel, P. F.; Groff-Kellermann, Birgit; Hoehn, Holger; Martin, George M.; Kubisch, Christian; Oshima, Junko

    2010-01-01

    Werner syndrome (WS) is an autosomal recessive segmental progeroid syndrome caused by null mutations at the WRN locus, which codes for a member of the RecQ family of DNA helicases. Since 1988, the International Registry of Werner syndrome had enrolled 130 molecularly confirmed WS cases from among 11

  6. Analysis of human chromosome 21 for a locus conferring susceptibility to Hirschsprung Disease

    Energy Technology Data Exchange (ETDEWEB)

    Bolk, S.; Duggan, D.J.; Chakravarti, A. [Case Western Reserve Univ., Cleveland, OH (United States)

    1994-09-01

    It has been estimated that approximately 5% of patients diagnosed with Hirschsprung disease (HSCR), or aganglionic megacolon, have trisomy 21. Since the incidence of Hirschsprung disease is 1/5000 live births and the incidence of trisomy 21 is approximately 1/1000 live births, the observed occurrence of HSCR in trisomy 21 is fifty times higher than expected. We propose that at least one locus on chromosome 21 predisposes to HSCR. Although at fifty times elevated risk, only 1% of Down Syndrome cases have HSCR. Thus additional genes or genetic events are necessary for HSCR to manifest in patients with trisomy 21. Based on segregation analysis, Badner et al. postulated that recessive genes may be responsible for up to 80% of HSCR. We postulate that at least one such gene is on chromosome 21 and increased homozygosity for common recessive HSCR mutations may be one cause for the elevated risk of HSCR in cases of trisomy 21. To map such a chromosome 21 locus, we are searching for segments of human chromosome 21 which are identical by descent from the parent in whom non-disjunction occurred. These segments will arise either from meiosis I (followed by a crossover between the centromere and the locus) or from meiosis II (followed by no crossovers). Nine nuclear families with a proband diagnosed with HSCR and Down Syndrome have been genotyped for 18 microsatellite markers spanning human chromosome 21q. In all nine cases analyzed thus far, trisomy 21 resulted from maternal non-disjunction at meiosis I. At this point no single IBD region is apparent. Therefore, additional families are being ascertained and additional markers at high density are being genotyped to map the HSCR locus.

  7. Global and local contributions to surface curva- ture of healthy corneas

    Directory of Open Access Journals (Sweden)

    Alan Rubin

    2012-12-01

    Full Text Available This paper demonstrates for several healthy eyes the application of a simple model to understanding local and global contributions to short-term variation in anterior and posterior corneal curvature. Multiple axial anterior and posterior corneal radii and central corneal thicknesses for the right eyes of 10 young subjects were determined over time using a rotating Scheimpflug camera (Oculus Pentacam. The axial radii were transformed to corneal powers, and also to curvatures that were referred to a mid-corneal surface such that local and global contributions to short-term variation could be analyzed quantitatively.When variation of the anterior and posterior corneal surfaces of several healthy eyes are studied in terms of curvatures (rather than powers it is the posterior surfaces that are more variable withthe global or macroscopic rather than local effects dominating. (Harris and Gillan found the same for an eye with mild keratoconus. This finding is opposite to that when variation is considered in terms of dioptric power where the anterior corneal surface usually appears more variable. Possible reasons for this finding includes firstly that the posterior corneal surface has to be measured through the air-tear interface and anterior corneal surface,and thus some uncertainty in measurements of the posterior surface may relate to this limitation. Secondly, no attempt was made here to mathematically align the multiple surfaces as determined per eye and thus we cannot be certain that precisely the same central corneal region was measured each time.Investigators need to carefully consider whether they are more interested in the optical or physical nature of variation in surfaces such as the cornea since studies of the optical effects require theanalysis to be performed in terms of dioptric powers and  symmetric dioptric power space whereas studies of physical variation in the topography of the cornea and the possible reasons for such variability

  8. Changes in biomechanical properties of the cornea after modified transepithelial crosslinking

    Directory of Open Access Journals (Sweden)

    I. B. Medvedev

    2016-01-01

    Full Text Available The aim of the study was to evaluate changes in biomechanical properties of the cornea after conducting transepithelial crosslinking with the prior application of a 40 % glucose solution.Materials and methods. Just studied the biomechanical properties of the corneas of six rabbits breed Chinchilla (12 eyes. 4 rabbit entered in the experimental group, in which in one eye glucose solution was applied on the cornea and allowed to stay for 10 minutes, followed by the instillation of 0.1 % Riboflavin solution for 30 minutes. On a couple of the rabbit eye was applied a solution of Riboflavin without prior instillation of glucose. Then carried out the procedure of irradiation according to the conventional technology with UV with a wavelength of 370 μm and a beam energy of 3.0 mW / cm2. Two rabbits (4 eyes were included in the control group, in which crosslinking was not performed. After 1 month the euthanasia of the animals was performed with subsequent enucleation for corneal research on a tensile testing machine. In the control and experimental group compared, the relaxation curves and the following parameters were analyzed: initial stress (MPa, equilibrium stress (MPa modulus of elasticity.Results and their discussion. After the crosslinking the rise of the initial stress (in the control group and 0.7+0.1 MPa, in the experimental and 1.5+0.2 1.3+0.3 MPa, respectively. The stress relaxation is fast (equilibrium stress value is reached after 250 sec. and after the administration of glucose for approximately 75 seconds, which means a greater rigidity of experimental group of samples. In the experimental groups significantly changed and the modulus of elasticity: its value has increased approximately in 2 times in comparison with control samples. The equilibrium stress values in the experimental groups were different from the zero value that also indicates a change in the chemical structure of the samples.Conclusions. Holding transepithelial of

  9. Clinical performance of KeraSoft® IC in irregular corneas

    Directory of Open Access Journals (Sweden)

    Su S

    2015-10-01

    Full Text Available Stephanie Su,1 Lynette Johns,2 Marjorie J Rah,3 Robert Ryan,1 Joseph Barr3 1Visionary Eye Associates of Rochester, Rochester, NY, USA; 2Custom Lab Channel Business, Bausch & Lomb Incorporated, Wilmington, MA, USA; 3Medical Affairs – Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: This study evaluated the clinical performance of KeraSoft® IC (KIC soft contact lenses in subjects with irregular corneas.Patients and methods: This was a 12-month, prospective, open-label, observational study, which enrolled 43 subjects who were 18 years of age or older with irregular corneas. Subjects were fit according to the KIC Fitting Manual (kerasoftic.com. After achieving best fit according to the fitting manual, lenses were assessed for comfort, vision, centration, rotation, and movement. Subjects were instructed to wear their lenses between 8 and 16 hours each day. Assessments at the exit visit included logMAR visual acuity with high and low contrast, spherocylindrical overrefraction, slit-lamp findings, adverse events, and subjective outcomes.Results: The average base curve was 8.17±0.32 mm (n=70 eyes, and the average diameter dispensed was 14.53±0.12 mm (n=70 eyes. From the baseline to 12 months, there was statistically significant improvement in logMAR visual acuity with high contrast (P=0.038, but no significant difference in low-contrast visual acuity was observed (P>0.05. Slit-lamp findings were ≤ grade 1 for the majority of subjects (89%. Two nonserious adverse events were reported for two of the 84 enrolled eyes (two subjects. At 12 months, subjects reported improvements from habitual baseline for comfort and vision, both upon insertion and just before removal of lenses.Conclusion: Clinical outcomes at 12 months showed good visual, safety, and subjective outcomes for subjects with corneal irregularities who wore KeraSoft® IC soft contact lenses. Keywords: irregular corneas, keratoconus, soft contact lenses, KeraSoft® IC

  10. Dumping Syndrome

    Science.gov (United States)

    ... System & How it Works Digestive Diseases A-Z Dumping Syndrome What is dumping syndrome? Dumping syndrome occurs when food, especially sugar, ... the colon and rectum—and anus. What causes dumping syndrome? Dumping syndrome is caused by problems with ...

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

    Science.gov (United States)

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

    2008-03-01

    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.

  12. Induction of morphological and electrophysiological changes in hamster cornea after in vitro interaction with trophozoites of Acanthamoeba spp.

    Science.gov (United States)

    Omaña-Molina, Maritza; Navarro-García, Fernando; González-Robles, Arturo; Serrano-Luna, José de Jesús; Campos-Rodríguez, Rafael; Martínez-Palomo, Adolfo; Tsutsumi, Víctor; Shibayama, Mineko

    2004-06-01

    Acanthamoeba castellani and Acanthamoeba polyphaga are free-living amebae that cause keratitis and granulomatous encephalitis in humans. We have analyzed the early morphological and electrophysiological changes occurring during the in vitro interaction of cultured amebae with intact or physically damaged corneas obtained from hamsters. Both species of Acanthamoeba produced similar cytopathic changes, as seen by light microscopy and scanning electron microscopy. After adhesion to the epithelial surface, trophozoites formed clumps and migrated toward the cell borders, causing the separation of adjacent cells at 1 h of coculture. At later stages (2 to 4 h), some amebae were found under desquamating epithelial cells whereas others were seen associated with damaged cells or forming amebostome-like structures to ingest detached epithelial cells. Control corneas incubated in culture medium conditioned with amebae showed a cytoplasmic vacuolization and blurring of the epithelial-stromal junction. The early stages of corneal epithelial damage caused by amebae were also analyzed by measuring the transepithelial resistance changes in corneas mounted in Ussing chambers. Both species of Acanthamoeba caused a rapid decrease in electrical resistance. The present observations demonstrate that under in vitro conditions, Acanthamoeba trophozoites rapidly cause significant damage to the corneal epithelium. Furthermore, in our experimental model, previous physical damage to the corneas was not a prerequisite for the development of amebic corneal ulcerations.

  13. Force analysis of bacterial transmission from contact lens cases to corneas, with the contact lens as the intermediary

    NARCIS (Netherlands)

    Qu, Wen-wen; Hooymans, Johanna MM; de Vries, Jacob; van der Mei, Henderina; Busscher, Hendrik

    2011-01-01

    PURPOSE. To determine the probability of transmission of a Staphylococcus aureus strain from a contact lens case, to the contact lens (CL) surfaces, to the cornea, on the basis of bacterial adhesion forces measured by using atomic force microscopy (AFM). METHODS. Adhesion forces between S. aureus st

  14. Optical properties of the human cornea : Shape and wave aberration measurements using the VU topographer and Scheimpflug photography

    NARCIS (Netherlands)

    Sicam, V.A.D.P.

    2007-01-01

    In this study, the optical properties of the human cornea was investigated. Two major developments were made because current measurement techniques need improvement First, the VU topographer, which uses a color coded pattern, was validated with real eye data showing better performance compare to co

  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...

  16. Cultured corneas show dendritic spread and restrict herpes simplex virus infection that is not observed with cultured corneal cells

    Science.gov (United States)

    Thakkar, Neel; Jaishankar, Dinesh; Agelidis, Alex; Yadavalli, Tejabhiram; Mangano, Kyle; Patel, Shrey; Tekin, Sati Zeynep; Shukla, Deepak

    2017-01-01

    Herpes simplex virus-1 (HSV-1) causes life-long morbidities in humans. While fever blisters are more common, occasionally the cornea is infected resulting in vision loss. A very intriguing aspect of HSV-1 corneal infection is that the virus spread is normally restricted to only a small fraction of cells on the corneal surface that connect with each other in a dendritic fashion. Here, to develop a comprehensive understanding of the susceptibility of human corneal epithelial (HCE) cells to HSV-1 infection, we infected HCE cells at three different dosages of HSV-1 and measured the outcomes in terms of viral entry, gene and protein expression, viral replication and cytokine induction. In cultured cells, infectivity and cytokine induction were observed even at the minimum viral dosage tested, while a more pronounced dose-restricted infectivity was seen in ex vivo cultures of porcine corneas. Use of fluorescent HSV-1 virions demonstrated a pattern of viral spread ex vivo that mimics clinical findings. We conclude that HCE cell cultures are highly susceptible to infection whereas the cultured corneas demonstrate a higher ability to restrict the infection even in the absence of systemic immune system. The restriction is helped in part by local interferon response and the unique cellular architecture of the cornea. PMID:28198435

  17. Corneal Sulfated Glycosaminoglycans and Their Effects on Trigeminal Nerve Growth Cone Behavior In Vitro: Roles for ECM in Cornea Innervation

    OpenAIRE

    Schwend, Tyler; Deaton, Ryan J.; Zhang, Yuntao; Caterson, Bruce; Conrad, Gary W.

    2012-01-01

    In this investigation, we describe differential spatiotemporal expression patterns of glycosaminoglycans KS, DS, and CSA/C during developmental stages of cornea innervation. We show that purified GAGs have divergent effects on trigeminal neuron behavior using in vitro neuronal explant cultures.

  18. Rearrangements at the 11p15 locus and overexpression of insulin-like growth factor-II gene in sporadic adrenocortical tumors

    Energy Technology Data Exchange (ETDEWEB)

    Gicquel, C.; Schneid, H.; Le Bouc, Y. [Hopital Trousseau, Paris (France); Bertagna, X.; Francillard-Leblond, M.; Luton, J.P.; Girard, F. [Hopital Cochin, Paris (France)

    1994-06-01

    Little is known about the pathophysiology of sporadic adrenocortical tumors in adults. Because loss of heterozygosity at the 11p15 locus has been described in childhood tumors, particularly in adrenocortical tumors associated with the Beckwith-Wiedemann syndrome, and because insulin-like growth factor-II (IGF-II) is a crucial regulator of fetal adrenal growth, the authors looked for structural analysis at the 11p15 locus and IGF-II gene expression in 23 sporadic adrenocortical adult tumors: 6 carcinomas (5 with Cushing`s syndrome and 1 nonsecreting) and 17 benign adenomas (13 with Cushing`s syndrome, 1 pure androgen secreting, and 3 nonsecreting). Twenty-one patients were informative at the 11p15 locus, and six (four carcinomas and two adenomas) of them (28.5%) exhibited 11p15 structural abnormalities in tumor DNA (five, a uniparental disomy and one, a mosaicism). In a single case that could be further studied, a paternal isodisomy was observed. Very high IGF-II mRNA contents were detected in seven tumors (30%; 5 of the 6 carcinomas and 2 of the 17 adenomas). They were particularly found in tumors with uniparental disomy at the 11p15 locus. Overall, a strong correlation existed between IGF-II mRNA contents and DNA demethylation at the IGF-II locus. These data show that genetic alterations involving the 11p15 locus were highly frequent in malignant tumors, but found only in rare adenomas. These results in combination with evidence for overexpression of IGF-II from the 11p15.5 locus suggest that abnormalities in structure and/or expression of the IGF-II gene play a role as a late event of a multistep process of tumorigenesis. 58 refs., 6 figs., 4 tabs.

  19. Automatic pterygium detection on cornea images to enhance computer-aided cortical cataract grading system.

    Science.gov (United States)

    Gao, Xinting; Wong, Damon Wing Kee; Aryaputera, Aloysius Wishnu; Sun, Ying; Cheng, Ching-Yu; Cheung, Carol; Wong, Tien Yin

    2012-01-01

    In this paper, we present a new method to detect pterygiums using cornea images. Due to the similarity of appearances and spatial locations between pterygiums and cortical cataracts, pterygiums are often falsely detected as cortical cataracts on retroillumination images by a computer-aided grading system. The proposed method can be used to filter out the pterygium which improves the accuracy of cortical cataract grading system. This work has three major contributions. First, we propose a new pupil segmentation method for visible wavelength images. Second, an automatic detection method of pterygiums is proposed. Third, we develop an enhanced compute-aided cortical cataract grading system that excludes pterygiums. The proposed method is tested using clinical data and the experimental results demonstrate that the proposed method can improve the existing automatic cortical cataract grading system.

  20. Cadmium toxicity to the cornea of pregnant rats: Electron microscopy and x-ray microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizuka, M.; McCarthy, K.J.; Kaye, G.I.; Fujimoto, S. (Univ. of Occupational and Environmental Health, School of Medicine, Kitakyushu (Japan))

    1990-05-01

    Cadmium toxicity to the cornea of pregnant rats was studied using the electron microscope and x-ray microanalyzer. In in-vivo experiments, severe corneal edema occurred in pregnant dams that received intraperitoneal injections of cadmium sulphate for 4 days during gestation, but not in nonpregnant rats. Prominent swelling of mitochondria and the occurrence of intra- and intercellular vacuoles in the corneal endothelium were observed only in pregnant dams. In in-vitro experiments, electron-dense deposits consisting of cadmium-oxine complexes were preferentially found in swollen mitochondria of the endothelial cells. Cadmium peaks were obtained from these deposits with x-ray microanalysis. These data suggest that the corneal edema observed after administration of cadmium may imply the disturbance of pump function and barrier function of the corneal endothelium due to the primary toxic effects of this metal on mitochondria.

  1. A simplified technique for in situ excision of cornea and evisceration of retinal tissue from human ocular globe.

    Science.gov (United States)

    Parekh, Mohit; Ferrari, Stefano; Di Iorio, Enzo; Barbaro, Vanessa; Camposampiero, Davide; Karali, Marianthi; Ponzin, Diego; Salvalaio, Gianni

    2012-06-12

    Enucleation is the process of retrieving the ocular globe from a cadaveric donor leaving the rest of the globe undisturbed. Excision refers to the retrieval of ocular tissues, especially cornea, by cutting it separate from the ocular globe. Evisceration is the process of removing the internal organs referred here as retina. The ocular globe consists of the cornea, the sclera, the vitreous body, the lens, the iris, the retina, the choroid, muscles etc (Suppl. Figure 1). When a patient is suffering from corneal damage, the cornea needs to be removed and a healthy one must be transplanted by keratoplastic surgeries. Genetic disorders or defects in retinal function can compromise vision. Human ocular globes can be used for various surgical procedures such as eye banking, transplantation of human cornea or sclera and research on ocular tissues. However, there is little information available on human corneal and retinal excision, probably due to the limited accessibility to human tissues. Most of the studies describing similar procedures are performed on animal models. Research scientists rely on the availability of properly dissected and well-conserved ocular tissues in order to extend the knowledge on human eye development, homeostasis and function. As we receive high amount of ocular globes out of which approximately 40% (Table 1) of them are used for research purposes, we are able to perform huge amount of experiments on these tissues, defining techniques to excise and preserve them regularly. The cornea is an avascular tissue which enables the transmission of light onto the retina and for this purpose should always maintain a good degree of transparency. Within the cornea, the limbus region, which is a reservoir of the stem cells, helps the reconstruction of epithelial cells and restricts the overgrowth of the conjunctiva maintaining corneal transparency and clarity. The size and thickness of the cornea are critical for clear vision, as changes in either of them

  2. 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

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

    Science.gov (United States)

    Alizadeh, Hassan; Tripathi, Trivendra; Abdi, Mahshid; Smith, Ashley Dawn

    2014-01-01

    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 (PAcanthamoeba 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.

  4. Turnover of bone marrow-derived cells in the irradiated mouse cornea

    Science.gov (United States)

    Chinnery, Holly R; Humphries, Timothy; Clare, Adam; Dixon, Ariane E; Howes, Kristen; Moran, Caitlin B; Scott, Danielle; Zakrzewski, Marianna; Pearlman, Eric; McMenamin, Paul G

    2008-01-01

    In light of an increasing awareness of the presence of bone marrow (BM)-derived macrophages in the normal cornea and their uncertain role in corneal diseases, it is important that the turnover rate of these resident immune cells be established. The baseline density and distribution of macrophages in the corneal stroma was investigated in Cx3cr1gfp transgenic mice in which all monocyte-derived cells express enhanced green fluorescent protein (eGFP). To quantify turnover, BM-derived cells from transgenic eGFP mice were transplanted into whole-body irradiated wild-type recipients. Additionally, wild-type BM-derived cells were injected into irradiated Cx3cr1+/gfp recipients, creating reverse chimeras. At 2, 4 and 8 weeks post-reconstitution, the number of eGFP+ cells in each corneal whole mount was calculated using epifluorescence microscopy, immunofluorescence staining and confocal microscopy. The total density of myeloid-derived cells in the normal Cx3cr1+/gfp cornea was 366 cells/mm2. In BM chimeras 2 weeks post-reconstitution, 24% of the myeloid-derived cells had been replenished and were predominantly located in the anterior stroma. By 8 weeks post-reconstitution 75% of the myeloid-derived cells had been replaced and these cells were distributed uniformly throughout the stroma. All donor eGFP+ cells expressed low to moderate levels of CD45 and CD11b, with approximately 25% coexpressing major histocompatibility complex class II, a phenotype characteristic of previous descriptions of corneal stromal macrophages. In conclusion, 75% of the myeloid-derived cells in the mouse corneal stroma are replenished after 8 weeks. These data provide a strong basis for functional investigations of the role of resident stromal macrophages versus non-haematopoietic cells using BM chimeric mice in models of corneal inflammation. PMID:18540963

  5. Ultraviolet-visible light spectral transmittance of rabbit corneas after riboflavin/ultraviolet-A (365 nm) corneal collagen cross-linking.

    Science.gov (United States)

    Hwang, Ho Sik; Kim, Man Soo

    2013-01-01

    To determine the effect of riboflavin/ultraviolet-A (365 nm) corneal collagen cross-linking on the transmission of the ultraviolet-visible (UV-VIS) light spectrum through the cornea. Twelve New Zealand white male rabbits were used in this research. Cross-linking was performed unilaterally on the right eyes of the animals while only the epithelium was removed on the left eyes as the control. Seven weeks after cross-linking, the animals were euthanized, and the enucleated eyes were processed for transmission spectroscopy. To confirm that the cross-linking procedures was done successfully on the right corneas, the tensile force-extension relationship was measured using six corneas from three of the rabbits after the transmission spectrum was determined. Seven weeks after cross-linking, ten of the 12 rabbits had clear corneas in the cross-linked and control eyes. The two rabbits with neovascularization and granular opacities in the right corneas were not included in subsequent measurements. In the cross-linked corneas, transmittance was 87.57% at 650 nm, and decreased continuously as the wavelength shortened. From 315 nm, the transmittance rapidly decreased and was 35.52% at 300 nm. In the control corneas, transmittance was 95.95% at 650 nm and decreased continuously as the wavelength shortened. Below 315 nm, the transmittance rapidly decreased, to 40.29% at 300 nm. The transmittance of the cross-linking corneas was 10%-20% lower than that of the control corneas. The difference was 8.38% at 650 nm and increased as the wavelength shortened, reaching a maximum of 20.59% at 320 nm, and decreased rapidly to 4.77% at 300 nm. The tensile force-extension relationship showed that a greater force was necessary to extend the cross-linking corneas over 500 µm than that of the control corneas. The transmittance of the cross-linked corneas was 10%-20% lower than that of the control corneas. The difference increased as the wavelength decrease, reaching a maximum at 320 nm and then

  6. 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

  7. Amniotic membrane covering promotes healing of cornea epithelium and improves visual acuity after debridement for fungal keratitis

    Institute of Scientific and Technical Information of China (English)

    Bo; Zeng; Ping; Wang; Ling-Juan; Xu; Xin-Yu; Li; Hong; Zhang; Gui-Gang; Li

    2014-01-01

    AIM:To investigate the effect of amniotic membrane covering(AMC) on the healing of cornea epithelium and visual acuity for fungal keratitis after debridement.METHODS:Twenty fungal keratitis patients were divided into two groups randomly, the AMC group and the control group, ten patients each group. Both debridement of the infected cornea tissue and standard anti-fungus drugs treatments were given to every patients, monolayer amniotic membrane were sutured to the surface of the entire cornea and bulbar conjunctiva with 10-0 nylon suture for patients in the AMC group.The diameter of the ulcer was determined with slit lamp microscope and the depth of the infiltration was determined with anterior segment optical coherence tomography. Uncorrected visual acuity(UCVA) was tested before surgery and three month after healing of the epithelial layer. The healing time of the cornea epithelium, visual acuity(VA) was compared between the two groups using t- test.RESULTS:There was no statistical difference of the diameter of the ulcer, depth of the infiltration, height of the hypopyon and VA between the two groups beforesurgery(P >0.05). The average healing time of the AMC group was 6.89 ±2.98 d, which was statistically shorter than that of the control group(10.23±2.78d)(P <0.05).The average UCVA of the AMC group was 0.138 ±0.083,which was statistically better than that of the control group(0.053±0.068)(P <0.05).CONCLUSION:AMC surgery could promote healing of cornea epithelium after debridement for fungal keratitis and lead to better VA outcome.

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

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, L.J.; Yen, P.; Pomerantz, D.; Martin, E.; Rolewic, L.; Mohandas, T. (Univ. of California, Los Angeles (USA))

    1989-11-01

    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{sup {minus}} 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.

  9. Brown–McLean syndrome: the role of iridodonesis

    Directory of Open Access Journals (Sweden)

    Suwan Y

    2016-04-01

    Full Text Available Yanin Suwan, Chaiwat Teekhasaenee, Kaevalin Lekhanont, Wasu Supakontanasan Department of Ophthalmology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand Purpose: The aim of this study was to report a case series of Brown–McLean syndrome (BMS.Methods: The charts of 28 patients with BMS at Ramathibodi and Rutnin Hospital from 1981 to 2015 were reviewed.Results: BMS is a rare condition with corneal edema involving the peripheral cornea with orange-brown pigment deposition underlying the edematous area. The edema typically starts inferiorly and advances circumferentially to superior cornea. Central cornea remains clear in most patients. We report 28 patients with BMS that occurred either spontaneously or after various intraocular procedures. Ultrasound biomicroscopy was performed to demonstrate the iridocorneal relationship.Conclusion: Iridocorneal relationship from the ultrasound biomicroscopy study in four patients did not support previous hypothesis about the role of iridodonesis impact on corneal endothelium. Patients with BMS can rarely progress to corneal decompensation; however, they should be periodically monitored and made aware of early clinical signs of their complications. Keywords: Brown–McLean syndrome, peripheral corneal edema, marginal corneal edema, corneal decompensation

  10. Use of Cross-linked Donor Corneas as Carriers for the Boston Keratoprosthesis

    Science.gov (United States)

    2016-10-03

    Chemical Injuries; Unspecified Complication of Corneal Transplant; Autoimmune Diseases; Ocular Cicatricial Pemphigoid; Stevens Johnson Syndrome; Lupus Erythematosus, Systemic; Rheumatoid Arthritis; Other Autoimmune Diseases

  11. 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

  12. Cushing syndrome

    Science.gov (United States)

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

  13. Serotonin syndrome

    Science.gov (United States)

    Hyperserotonemia; Serotonergic syndrome; Serotonin toxicity; SSRI - serotonin syndrome; MAO - serotonin syndrome ... two medicines that affect the body's level of serotonin are taken together at the same time. The ...

  14. OrbscanⅡ角膜地形图系统筛查亚临床期圆锥角膜%Screening of Subclinical Keratoconus by OrbscanⅡ Cornea Topography

    Institute of Scientific and Technical Information of China (English)

    虞林丽; 赵刚平; 朱敏; 王艳华; 李追; 赵岭江; 张亚军

    2012-01-01

    Objective To evaluate the features of cornea topography in subclinical keratoconus. Methods Orbscan II cornea topography system was performed on 15 patients(26 eyes) with subclinical keratoconus. Diff values of cornea anterior surface and posterior surface, thickness of the thinnest cornea, center refractive power of cornea, and simulated keratometry were measured. Results Diff values of cornea anterior surface and posterior surface in subclinical keratoconus were 0. 025 and 0. 050 mm respectively, thickness of the thinnest cornea was (450.65 + 35.67) μm;SimK was (4. 55 + 1. 09)D, and center refractive power of cornea was (47. 1 ±3. 5) D. Diff value of cornea anterior surface had a positive correlation with diff value of cornea posterior surface and center refractive power of cornea. Conclusion Orbscan JJ cornea topography system can provide morphological basis for early diagnosis of subclinical keratoconus.%目的 研究亚临床期圆锥角膜的角膜地形图改变的特点.方法 应用 OrbscanⅡ角膜地形图系统检测15例(26只眼)亚临床期圆锥角膜患者的角膜,得到角膜前表面和后表面Diff 值、角膜最薄点厚度、角膜中央屈光力及角膜模拟镜差值(SimK 值),了解亚临床期圆锥角膜的敏感性指标以及各指标之间的相关关系.结果 亚临床期圆锥角膜的角膜前表面Diff 值是0.025 mm,角膜后表面Diff 值为0.050 mm;角膜最薄点厚度(450.65±35.67)μm;SimK值为(4.55±1.09)D;角膜中央屈光力为(47.1 ±3.5)D.角膜前表面Diff值与角膜后表面Diff值、角膜中央屈光力呈正相关关系;角膜后表面Diff值与角膜中央屈光力呈正相关关系.结论 OrbscanⅡ角膜地形图系统可为早期诊断亚临床期圆锥角膜提供形态学依据.

  15. Meningioma in Down Syndrome.

    Science.gov (United States)

    Yamamoto, Takahiro; Shinojima, Naoki; Todaka, Tatemi; Nishikawa, Shigeyuki; Yano, Shigetoshi; Kuratsu, Jun-ichi

    2015-09-01

    Down syndrome comprises multiple malformations and is due to trisomy of chromosome 21. There is epidemiologic evidence that individuals with Down syndrome are at decreased risk for solid tumors including brain tumors. It has been suggested that some genes expressed on the extra copy of chromosome 21 act as tumor suppressor genes and contribute to protection against tumorigenesis. We report the first case to our knowledge of a patient with Down syndrome, an 8-year-old boy, with an intracranial meningioma, in which the status of chromosome 21 was examined. The diagnosis was based on histologic examination of the surgically resected tumor. Postoperatively, the patient's neurologic status improved, and there was no tumor regrowth in the next 2 years. Fluorescence in situ hybridization for chromosome 22 confirmed high allele loss involving the neurofibromin 2 gene locus, a finding typical in meningiomas. Fluorescence in situ hybridization also revealed chromosome 21 heterogeneity in tumor cells; not only cells with trisomy 21 but also cells with disomy and monosomy 21 were present. All blood cells from the patient manifested trisomy 21. Deletion of the chromosome 21 allele may be associated with tumorigenesis of meningioma in Down syndrome. This supports the hypothesis that some genes whose expression is increased on the extra copy of chromosome 21 function as tumor suppressor genes and that they contribute to the reduced tumor incidence in individuals with Down syndrome. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Regulatory organization of the staphylococcal sae locus.

    Science.gov (United States)

    Adhikari, Rajan P; Novick, Richard P

    2008-03-01

    This paper describes an investigation of the complex internal regulatory circuitry of the staphylococcal sae locus and the impact of modifying this circuitry on the expression of external genes in the sae regulon. The sae locus contains four genes, the saeR and S two-component signalling module (TCS), and saeP and Q, two upstream genes of hitherto unknown function. It is expressed from two promoters, P(A)sae, which transcribes only the TCS, and P(C)sae, which transcribes the entire locus. A bursa aurealis (bursa) transposon insertion in saeP in a derivative of Staphylococcus aureus NCTC 8325 has a profound effect on sae function. It modifies the activity of the TCS, changing the expression of many genes in the sae regulon, even though transcription of the TCS (from P(A)sae) is not interrupted. Moreover, these effects are not due to disruption of saeP since an in-frame deletion in saeP has essentially no phenotype. The phenotype of S. aureus strain Newman is remarkably similar to that of the saeP : : bursa and this similarity is explained by an amino acid substitution in the Newman saeS gene that is predicted to modify profoundly the signalling function of the protein. This concurrence suggests that the saeP : : bursa insertion affects the signalling function of saeS, a suggestion that is supported by the ability of an saeQR clone, but not an saeR clone, to complement the effects of the saeP : : bursa insertion.

  17. 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.

  18. 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 lines of self-intersections of the front in the parametric space. This becomes possible by using the deformable simplicial complexes (DSC, [1]) method for deformable interface tracking. DSC provide a simple collision detection mechanism, allows for interface topology control, and does not require...

  19. Immunogenicity of a Moraxella bovis bacterin containing attachment and cornea-degrading enzyme antigens.

    Science.gov (United States)

    Gerber, J D; Selzer, N L; Sharpee, R L; Beckenhauer, W H

    1988-02-01

    An adjuvanted Moraxella bovis bacterin containing attachment antigens and cornea-degrading enzyme antigens protected cattle from infectious bovine keratoconjunctivitis (IBK) when experimentally challenged with homologous and heterologous challenge cultures of M. bovis. This bacterin also protected cattle against field exposure to M. bovis. Transmission electron microscopy and fluorescein labeled anti-M. bovis pili antiserum showed pili on the M. bovis bacterin strain. Scanning electron microscopy demonstrated a fibrillar glycocalyx. The bacterin strain of M. bovis, but not all strains of M. bovis, destroyed bovine corneal cell monolayers in vitro. Bovine corneal cells began to separate from each other within 5 min after M. bovis organisms were added and adhered to the cell monolayers. Moraxella bovis organisms remained attached to the disintegrating cells as the cell membrane separated and was digested. Vaccination stimulated bacterial agglutination antibodies. However, protection against experimental challenge was more closely related to the cornea-degrading enzyme content of the experimental bacterins. Twenty-two of 29 cattle (76%) vaccinated with bacterins containing a relative enzyme activity (REA) greater than 0.4 were protected in a rigorous challenge of immunity test. Only 1 of 21 non-vaccinated calves (5%) was free of IBK. Ninety-two percent (24/26) of calves vaccinated with a bacterin containing a REA greater than 0.29 remained free of IBK following field exposure, whereas 47% (8/17) non-vaccinated calves developed IBK. Only 8 of 12 calves (67%) vaccinated with a bacterin containing a REA of 0.09 remained free of IBK. In a larger field efficacy test consisting of 32 herds in six states, the incidence of IBK in individual herds ranged from 0% to 55%. The overall rate of infection was 11.2%. Vaccination of calves with an M. bovis bacterin that contained a REA of 0.63 reduced the incidence of IBK from 11.2% (217/1931) in the non-vaccinated controls to 4

  20. In-Vivo Slit Scanning Confocal Microscopy of Normal Corneas in Indian Eyes

    Directory of Open Access Journals (Sweden)

    Vanathi Murugesan

    2003-01-01

    Full Text Available Objective: To study the cellular populations of healthy corneas of Indian eyes using confocal microscopy and to evaluate the correlation with age, gender and laterality. Methods: The central corneas of 100 eyes of 50 healthy subjects were examined using an i n-vivo slit scanning confocal microscope (Confoscan 2. Images were analysed for cell densities of the epithelium, stroma and endothelium. Results: Good quality images enabling analysis of all cell layer populations were obtained in 74 eyes of 43 healthy subjects (22 males and 21 females with a mean age of 31.89 ± 13.47 (range 19-71 years. The basal epithelial cell density was 3601.38 ± 408.19 cells/mm2 (range 3017.3 -4231.1cells/mm2. The mean keratocyte nuclei density in the anterior stroma was 1005.02 ± 396.86 cells/mm2 (range 571.6 - 1249.6 cells/mm2 and in the posterior stroma was 654.32 ± 147.09 cells/mm2 (range 402.6 - 1049.1 cells/mm2. Posterior keratocyte nuclei density was 30.76% less than the anterior stromal keratocyte nuclei density. The difference in keratocyte nuclei density was statistically significant (P=0.001. The mean endothelial cell density was 2818.1 ± 361.03 cells/mm2 (range 2118.9 - 4434 cells/mm2 and the mean endothelial cell area was found to be 385.44 ± 42.66 mm2 (range 268.9 - 489.2 mm2. Hexagonal cells formed 22.5 - 69.4% of the endothelial cell populations (mean 42.04 ± 11.81%. Mean coefficient of cell size variation was 32.29 ± 3.06 (range 27.2 - 39.2. No statistically significant differences were found in cell densities of any corneal layer either between female and male patients or between right and left eyes. Basal epithelial cell density, anterior stromal keratocyte nuclei and posterior stromal keratocyte nuclei density were unaffected by age (r= 0.12, 0.07, - 0.12 respectively (P= 0.001. There was a statistically significant negative correlation between mean endothelial cell density and increase in age (r= - 0.42, P=0.001. Coefficient of cell size

  1. Gardner Syndrome

    Science.gov (United States)

    ... Home > Types of Cancer > Gardner Syndrome Request Permissions Gardner Syndrome Approved by the Cancer.Net Editorial Board , 06/2014 What is Gardner syndrome? Gardner syndrome is a subtype of familial ...

  2. 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.

  3. 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.

  4. Inside the CBF locus in Poaceae.

    Science.gov (United States)

    Tondelli, Alessandro; Francia, Enrico; Barabaschi, Delfina; Pasquariello, Marianna; Pecchioni, Nicola

    2011-01-01

    Several molecular evidences have been gathered in Poaceae that point out a central role of the CBF/DREB1 transcription factors in the signal transduction pathways leading to low-temperature tolerance, although to a quite different extent between crops originating from either temperate or tropical climates. A common feature of the CBF/DREB1 genes in Poaceae is their structural organization at the genome level in clusters of tandemly duplicated genes. In temperate cereals such as barley and wheat, expansion of specific multigene phylogenetic clades of CBFs that map at the Frost Resistance-2 locus has been exclusively observed. In addition, copy number variants of CBF genes between frost resistant and frost sensitive genotypes raise the question if multiple copies of the CBF/DREB1s are required to ensure freezing tolerance. On the other hand, in crops of tropical origin such as rice and maize, a smaller or less-responsive CBF regulon may have evolved, and different mechanisms might determine chilling tolerance. In this review, recent advances on the organization and diversity at the CBF cluster locus in the grasses are provided and discussed. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  5. Disruption of the ugt1 locus in mice resembles human Crigler-Najjar type I disease.

    Science.gov (United States)

    Nguyen, Nghia; Bonzo, Jessica A; Chen, Shujuan; Chouinard, Sarah; Kelner, Michael J; Hardiman, Gary; Bélanger, Alain; Tukey, Robert H

    2008-03-21

    The 9 UDP-glucuronosyltranferases (UGTs) encoded by the UGT1 locus in humans are key enzymes in the metabolism of most drugs as well as endogenous substances such as bile acids, fatty acids, steroids, hormones, neurotransmitters, and bilirubin. Severe unconjugated hyperbilirubinemia in humans that suffer from Crigler-Najjar type I disease results from lesions in the UGT1A1 gene and is often fatal. To examine the physiological importance of the Ugt1 locus in mice, this locus was rendered non-functional by interrupting exon 4 to create Ugt1(-/-) mice. Because UGT1A1 in humans is responsible for 100% of the conjugated bilirubin, it followed that newborn Ugt1(-/-) mice developed serum levels of unconjugated bilirubin that were 40-60 times higher than Ugt1(+/-) or wild-type mice. The result of extreme unconjugated bilirubin in Ugt1(-/-) mice, comparable to the induced levels noted in patients with Crigler-Najjar type 1 disease, is fatal in neonatal Ugt1(-/-) mice within 2 weeks following birth. The extreme jaundice is present as a phenotype in skin color after 8 h. Neonatal Ugt1(-/-) mice exhibit no detectable UGT1A-specific RNA, which corresponds to a complete absence of UGT1A proteins in liver microsomes. Conserved glucuronidation activity attributed to the Ugt1 locus can be defined in Ugt1(-/-) mice, because UGT2-dependent glucuronidation activity is unaffected. Remarkably, the loss of UGT1A functionality in liver results in significant alterations in cellular metabolism as investigated through changes in gene expression. Thus, the loss of UGT1A function in Ugt1(-/-) mice leads to a metabolic syndrome that can serve as a model to further investigate the toxicities associated with unconjugated bilirubin and the impact of this disease in humans.

  6. Papillon-Lefevre Syndrome: A Case Report

    Directory of Open Access Journals (Sweden)

    Sanchita Kundu Shabnam Zahir

    2012-07-01

    Full Text Available Papillon-Lefevre Syndrome is a very rare syndrome of autosomal recessiveinheritance characterized by palmer-planter hyperkeratosis and early onset of a severedestructive periodontitis., leading to premature loss of both primary and permanentdentitions.Genetic studies have shown that mutations in the major gene locus ofchromosome 11q14 with loss of function of cathepsin C gene are responsible for thissyndrome. An early diagnosis and intervention can help to preserve teeth and preventtheir premature exfoliation. A clinical case of Papillon- Lefevre syndrome isdiscussed herewith having all of the characteristic features.

  7. Keratinocyte Growth Factor-2 on the Proliferation of Corneal Epithelial Stem Cells in Rabbit Alkali Burned Cornea

    Institute of Scientific and Technical Information of China (English)

    Liu; Yongping; Shuqi; Huang; Jianxian; Lin; Wenxin; Zhang

    2007-01-01

    Purpose: To determine whether the topical application of keratinocyte growth factor-2 (KGF-2) can enhance corneal epithelial healing in rabbit alkali burned cornea. In addition, the distribution and proliferation of corneal epithelial stem cells in KGF-2-treated and control corneas were investigated to explain their mechanisms of effects on the epithelium.Methods: Twenty-four New Zealand eyes were divided into four groups, treated with KGF-2 solution (1, 50, 100 μg/ml) and PBS solution. Eighth millimeter filter paper discs, produced by standard paper punch, were soaked for 15 sec in 0.5N NaOH solution. The alkali-soaked discs were applied to the central cornea, centered on the pupil and held gently in position with forceps for 1 min. The cornea was finally irrigated over 1 min with 100 ml balanced salt solution (BSS). Keratinocyte growth factor-2 was then applied topically three times a day. The phosphate-buffered saline (PBS) group was served as a control. Each corneal epithelial defect was subsequently photographed every 24 hours with a slit lamp and was measured by computer-assisted digitizer. In each group, two rabbits were sacrificed for light microscopic examination after the interval of 7, 14 and 21 days. Meanwhile, the cornea epithelium was examined by immunohistochemistry for P63, AE5, EGFR.Results: Topical application of 10 μg/ml to 100 μg/ml KGF-2 significantly accelerated corneal epithelial wound healing when compared with controls. After 24 hours,epithelial healing rate of the 100 μg/ml KGF-2 group and the PBS treated group was (74±6)% and (40±8)% (P < 0.05). After 48 hours, the rate of the C group was (94±6)%, whereas in the control group it was (73±12)% (P < 0.05). Epithelial defects were often recurrent, which happened only two times in the 100 μg/ml KGF-2-treated group, but many times in the control group. In the corneal epithelial stem cell analysis, the number of the P63 positive cells was higher in the KGF-2-treated corneal

  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. 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 fibroblast expression microarrays from patients with PRDM5 mutations p.Arg590* and Δ exons 9-14, as well as from a PRDM5 ChIP-sequencing experiment. Gene ontology analysis of dysregulated PRDM5 target genes reveals enrichment for extracellular matrix (ECM) genes supporting vascular integrity...... and development. Q-PCR, and ChIP-qPCR confirm upregulation of critical mediators of ECM stability in vascular structures (COL13A1, COL15A1, NTN1, CDH5) in patient fibroblasts. We identify H3K9 di-methylation at these PRDM5 target genes in fibroblasts, and demonstrate that the BCS2 mutation p.Arg83Cys diminishes...

  10. Magic angle-enhanced MRI of fibrous microstructures in sclera and cornea with and without intraocular pressure loading.

    Science.gov (United States)

    Ho, Leon C; Sigal, Ian A; Jan, Ning-Jiun; Squires, Alexander; Tse, Zion; Wu, Ed X; Kim, Seong-Gi; Schuman, Joel S; Chan, Kevin C

    2014-08-07

    The structure and biomechanics of the sclera and cornea are central to several eye diseases such as glaucoma and myopia. However, their roles remain unclear, partly because of limited noninvasive techniques to assess their fibrous microstructures globally, longitudinally, and quantitatively. We hypothesized that magic angle-enhanced magnetic resonance imaging (MRI) can reveal the structural details of the corneoscleral shell and their changes upon intraocular pressure (IOP) elevation. Seven ovine eyes were extracted and fixed at IOP = 50 mm Hg to mimic ocular hypertension, and another 11 eyes were unpressurized. The sclera and cornea were scanned at different angular orientations relative to the main magnetic field inside a 9.4-Tesla MRI scanner. Relative MRI signal intensities and intrinsic transverse relaxation times (T2 and T2*) were determined to quantify the magic angle effect on the corneoscleral shells. Three loaded and eight unloaded tendon samples were scanned as controls. At magic angle, high-resolution MRI revealed distinct scleral and corneal lamellar fibers, and light/dark bands indicative of collagen fiber crimps in the sclera and tendon. Magic angle enhancement effect was the strongest in tendon and the least strong in cornea. Loaded sclera, cornea, and tendon possessed significantly higher T2 and T2* than unloaded tissues at magic angle. Magic angle-enhanced MRI can detect ocular fibrous microstructures without contrast agents or coatings and can reveal their MR tissue property changes with IOP loading. This technique may open up new avenues for assessment of the biomechanical and biochemical properties of ocular tissues in aging and in diseases involving the corneoscleral shell. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  11. Magic Angle–Enhanced MRI of Fibrous Microstructures in Sclera and Cornea With and Without Intraocular Pressure Loading

    Science.gov (United States)

    Ho, Leon C.; Sigal, Ian A.; Jan, Ning-Jiun; Squires, Alexander; Tse, Zion; Wu, Ed X.; Kim, Seong-Gi; Schuman, Joel S.; Chan, Kevin C.

    2014-01-01

    Purpose. The structure and biomechanics of the sclera and cornea are central to several eye diseases such as glaucoma and myopia. However, their roles remain unclear, partly because of limited noninvasive techniques to assess their fibrous microstructures globally, longitudinally, and quantitatively. We hypothesized that magic angle–enhanced magnetic resonance imaging (MRI) can reveal the structural details of the corneoscleral shell and their changes upon intraocular pressure (IOP) elevation. Methods. Seven ovine eyes were extracted and fixed at IOP = 50 mm Hg to mimic ocular hypertension, and another 11 eyes were unpressurized. The sclera and cornea were scanned at different angular orientations relative to the main magnetic field inside a 9.4-Tesla MRI scanner. Relative MRI signal intensities and intrinsic transverse relaxation times (T2 and T2*) were determined to quantify the magic angle effect on the corneoscleral shells. Three loaded and eight unloaded tendon samples were scanned as controls. Results. At magic angle, high-resolution MRI revealed distinct scleral and corneal lamellar fibers, and light/dark bands indicative of collagen fiber crimps in the sclera and tendon. Magic angle enhancement effect was the strongest in tendon and the least strong in cornea. Loaded sclera, cornea, and tendon possessed significantly higher T2 and T2* than unloaded tissues at magic angle. Conclusions. Magic angle–enhanced MRI can detect ocular fibrous microstructures without contrast agents or coatings and can reveal their MR tissue property changes with IOP loading. This technique may open up new avenues for assessment of the biomechanical and biochemical properties of ocular tissues in aging and in diseases involving the corneoscleral shell. PMID:25103267

  12. The role of connective tissue growth factor, transforming growth factor β1 and Smad signaling pathway in cornea wound healing

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The cornea is a highly specialized and unique organ in the human body. Its main function is to project light from the external environment onto the retina, and it has a specific transparency to perform its function properly. The transparency and integrity of the cornea is of vital importance. The corneal wound, especially laceration deep to Bowman's membrane and stroma, which will inevitably cause scar formation, may cause the degeneration or even loss of sight. Injury can activate many biological factors in cornea as a strong stimulating signal. Transforming growth factors (TGF) and connective tissue growth factors (CTGF) are thought to be related to scar formation after injury. TGF can stimulate stroma cells of cornea and promote synthesis of matrix. Over expression of TGF causes scar formation.1,2 CTGF is a 38 kD cysteine-rich protein molecule and belongs to CCN family (CTGF/Fisp12, Cyr 61/CEF-10, Nov). In 1991, CTGF was firstly found in endothelial cells of human umbilical vein cultured in vitro.3,4 CTGF acts as an important molecule that intermediates the processes of fibrosis, scarring, wound repairing, angiogenesis and embryonic development in many cell types. CTGF plays a unique role in proliferation, differentiation and adhesion of fibroblast cells, which in turn produces large amounts of collagen and other extracellular matrix (ECM) proteins.5-8 CTGF is upregulated in fibrotic diseases, including lung-, skin-, pancreas-, liver-and kidney fibrosis.9,10 This study reports the expressions and interactions of TGF-β1 and CTGF in corneal wound in vivo. This study aimed at determining the expressions and interactions of CTGF and TGF-β1 in Smad signaling pathway during the period when corneal wound was healing.

  13. Comment on amniotic membrane covering promotes healing of cornea epithelium and improves visual acuity after debridement for fungal keratitis

    Institute of Scientific and Technical Information of China (English)

    Ahmet; Tas; Abdullah; Ilhan; Umit; Yolcu; Uzeyir; Erdem

    2015-01-01

    <正>Dear Editor,We congratulate Zeng et al[1]for their study entitled"Amniotic membrane covering promotes healing of cornea epithelium and improves visual acuity after debridement for fungal keratitis".The authors endeavored to present an alternative method for ophthalmologists in the treatment of a challenging case.We would like to express our reservations and ask for the attitudes of the authors about

  14. Commercially available rigid gas-permeable contact lens for protecting the cornea from drying during vitrectomy with a wide viewing system

    OpenAIRE

    Kamei M; Matsumura N; Sakaguchi H; Oshima Y; Ikuno Y; Nishida K

    2012-01-01

    Motohiro Kamei, Nagakazu Matsumura, Hirokazu Sakaguchi, Yusuke Oshima, Yasushi Ikuno, Kohji NishidaDepartment of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, JapanPurpose: We evaluated the usefulness of commercially available materials for protecting the cornea from drying during vitrectomy with a wide-angle viewing system.Methods: Three vitreoretinal surgeons evaluated fundus visibility during vitrectomy on the images of five study materials used on the cornea: balance...

  15. Clinical Correlation between Placido, Scheimpflug and LED Color Reflection Topographies in Imaging of a Scarred Cornea

    Directory of Open Access Journals (Sweden)

    Anastasios John Kanellopoulos

    2014-10-01

    Full Text Available This case report aims to evaluate safety, efficacy and feasibility of anterior surface imaging by a novel point-source reflection topographer, in comparison to four other corneal imaging modalities. A 17-year-old female patient, clinically diagnosed with chronic herpetic keratitis in her left eye was imaged by a novel multicolored-spot reflection topography system. We comparatively investigated elevation and curvature maps between the novel topographer and established Placido disk topography and Scheimpflug tomography systems. Pachymetry maps were compared between the Scheimpflug system and anterior-segment optical coherence tomography system. The Placido system failed to properly register the abnormal anterior surface due to incomplete mire registration, while the Scheimpflug topometry device imaged the anterior surface properly, but not the posterior (due to media opacity, and thus pachymetry was highly irregular and erroneous in this case. Imaging of corneas infected with herpes simplex virus keratitis has been rare; we have not identified any such documentation in the peer review literature in the last 10 years. This novel multicolored-spot reflection topography imaging may offer successful corneal imaging in cases where established clinical topography systems may fail to produce accurate reconstruction of the corneal shape. This is an important case demonstrating exceptional clinical feasibility in such rare cases offered by a newly introduced technology in ophthalmic imaging.

  16. 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

    2016-07-20

    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.

  17. Why don't we have enough cornea donors? A literature review and survey.

    Science.gov (United States)

    Golchet, G; Carr, J; Harris, M G

    2000-05-01

    Organ donation provides a second chance for those who have experienced severe disease or injury. Unfortunately there is a huge discrepancy between the supply and demand of transplantable organs, despite the existence of sufficient numbers of potential donors. Through a review of the literature and a survey of optometry students, this article provides insight into the reasons for the shortage of corneal donors and how more corneal donors might be obtained. A survey of 200 optometry students at the University California, Berkeley, School of Optometry was conducted to augment the literature review. Seventy-six students (38% of those surveyed) completed the survey process. Results of the survey indicated that 64.5% of who responded were willing to donate body organs, while 31.6% were not. Of those not willing to donate organs, 11.8% cited religious reasons. Other personal reasons included: fear (4%), respect for the human body (7.9%), and parental disapproval (6.4%). Only 46.1% of respondents had donation stickers on their driver's licenses. The literature review and survey indicate that age, religion, culture, personality characteristics, views on death and mortality, body image, and humanitarian concerns are among the many factors that influence people's opinion concerning organ donations. Education of the public and health care professionals' awareness of the importance of obtaining corneas for donation is crucial to end the shortage of organ donors.

  18. Q pili enhance the attachment of Moraxella bovis to bovine corneas in vitro.

    Science.gov (United States)

    Ruehl, W W; Marrs, C; Beard, M K; Shokooki, V; Hinojoza, J R; Banks, S; Bieber, D; Mattick, J S

    1993-01-01

    Moraxella bovis, the causative agent of infectious bovine keratoconjunctivitis, exhibits several virulence factors, including pili, haemolysin, leukotoxin, and proteases. The pili are filamentous appendages which mediate bacterial adherence. Prior studies have shown that Q-piliated M. bovis Epp63 are more infectious and more pathogenic than I-piliated and non-piliated isogenic variants, suggesting that Q pili per se, or traits associated with Q-pilin expression, promote the early association of Q-piliated bacteria with bovine corneal tissue. In order to better evaluate the role of Q pili in M. bovis attachment, several M. bovis strains and a recombinant P. aeruginosa strain which elaborates M. bovis Q pili but not P. aeruginosa PAK pili, were evaluated using an in vitro corneal attachment assay. For each strain tested, piliated organisms attached better than non-piliated bacteria. M. bovis Epp63 Q-piliated bacteria adhered better than either the I-piliated or non-piliated isogenic variants. Finally, recombinant P. aeruginosa organisms elaborating M. bovis Q pili adhered better than the parent P. aeruginosa strain which did not produce M. bovis pili. These results indicate that the presence of pili, especially Q pili, enhances the attachment of bacteria to bovine cornea in vitro.

  19. Examination of tear film smoothness on corneae after refractive surgeries using a noninvasive interferometric method

    Science.gov (United States)

    Szczesna, Dorota H.; Kulas, Zbigniew; Kasprzak, Henryk T.; Stenevi, Ulf

    2009-11-01

    A lateral shearing interferometer was used to examine the smoothness of the tear film. The information about the distribution and stability of the precorneal tear film is carried out by the wavefront reflected from the surface of tears and coded in interference fringes. Smooth and regular fringes indicate a smooth tear film surface. On corneae after laser in situ keratomileusis (LASIK) or radial keratotomy (RK) surgery, the interference fringes are seldom regular. The fringes are bent on bright lines, which are interpreted as tear film breakups. The high-intensity pattern seems to appear in similar location on the corneal surface after refractive surgery. Our purpose was to extract information about the pattern existing under the interference fringes and calculate its shape reproducibility over time and following eye blinks. A low-pass filter was applied and correlation coefficient was calculated to compare a selected fragment of the template image to each of the following frames in the recorded sequence. High values of the correlation coefficient suggest that irregularities of the corneal epithelium might influence tear film instability and that tear film breakup may be associated with local irregularities of the corneal topography created after the LASIK and RK surgeries.

  20. Novel GLA Deletion in a Cypriot Female Presenting with Cornea Verticillata

    Directory of Open Access Journals (Sweden)

    Theodoros Georgiou

    2016-01-01

    Full Text Available Fabry disease is an X-linked lysosomal storage disorder resulting from a deficiency of the hydrolytic enzyme α-galactosidase A (α-Gal-A. It is characterized by progressive lysosomal accumulation of globotriaosylceramide (Gb3 and multisystem pathology, affecting the skin, nervous and cerebrovascular systems, kidneys, and heart. Heterozygous females typically exhibit milder symptoms and a later age of onset than males. Rarely, they may be relatively asymptomatic throughout a normal life span or may have symptoms as severe as those observed in males with the classic phenotype. We report on a 17-year-old female in whom cornea verticillata was found during a routine ophthalmological examination but with no other clinical symptoms. Leucocyte α-galactosidase activity was within the overlap range between Fabry heterozygotes and normal controls. Sanger sequencing of the GLA gene failed to reveal any pathogenic variants. Multiplex Ligation-dependent Probe Amplification (MLPA analysis revealed a deletion of exon 7. Using a long-range PCR walking approach, we managed to identify the deletion breakpoints. The deletion spans 1182 bp, with its 5′ end located within exon 6 of the GLA gene and its 3′ end located 612 bp downstream of exon 7. This finding represents a novel deletion identified in the first reported Cypriot female carrier of Fabry disease.

  1. Feasibility of quantitatively diagnosing cornea infection using Raman spectroscopy (Conference Presentation)

    Science.gov (United States)

    Bai, Yanru; Chen, Keren; Mishra, Arti; Beuerman, Roger; Liu, Quan

    2017-02-01

    Ocular infection is a serious eye disease that could lead to blindness without prompt and proper treatment. In pathology, ocular infection is caused by microorganisms such as bacteria, fungi or viruses. The essential prerequisite for the optimal treatment of ocular infection is to identify the microorganism causing infection early as each type of microorganism requires a different therapeutic approach. The clinical procedure for identifying the microorganism species causing ocular infection includes Gram staining (for bacteria)/microscopy (for fungi) and the culture of corneal surface scraping, or aqueous and vitreous smear samples taken from the surface of infected eyes. The culture procedure is labor intensive and expensive. Moreover, culturing is time consuming, which usually takes a few days or even weeks. Such a long delay in diagnosis could result in the exacerbation of patients' symptoms, the missing of the optimal time frame for initiating treatment and subsequently the rising cost for disease management. Raman spectroscopy has been shown highly effective for non-invasive identification of both fungi and bacteria qualitatively. In this study, we investigate the feasibility of identifying the microorganisms of ocular infection and quantifying the concentrations using Raman spectroscopy by measuring not only gram negative and gram positive bacteria but also infected cornea. By applying a modified orthogonal projection approach, the relative concentration of each bacteria species could be quantified. Our results indicate the great potential of Raman spectroscopy as an alternative tool for non-invasive diagnosis of ocular infection and could play a significantly role in future ophthalmology.

  2. Birefringence of the central cornea in children assessed with scanning laser polarimetry

    Science.gov (United States)

    Irsch, Kristina; Shah, Ashesh A.

    2012-08-01

    Corneal birefringence is a well-known confounding factor with all polarization-sensitive technology used for retinal scanning and other intraocular assessment. It has been studied extensively in adults, but little is known regarding age-related differences. Specifically, no information is available concerning corneal birefringence in children. For applications that are geared towards children, such as retinal birefringence scanning for strabismus screening purposes, it is important to know the expected range of both corneal retardance and azimuth in pediatric populations. This study investigated central corneal birefringence in children (ages three and above), by means of scanning laser polarimetry (GDx-VCC™, Carl Zeiss Meditec, Inc.). Children's measures of corneal retardance and azimuth were compared with those obtained in adults. As with previous studies in adults, corneal birefringence was found to vary widely in children, with corneal retardance ranging from 10 to 77 nm, and azimuth (slow axis) ranging from -11° to 71° (measured nasally downward). No significant differences in central corneal birefringence were found between children and adults, nor were significant age-related differences found in general. In conclusion, establishing knowledge of the polarization properties of the central cornea in children allows better understanding, exploitation, or bypassing of these effects in new polarization-sensitive pediatric ophthalmic applications.

  3. The surgical repair of the cornea of the dog using pericardium as a keratoprosthesis

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio de Moraes Barros

    1995-12-01

    Full Text Available Significant advances in corneal repair have been made in the past. Tissue graft has been used to repair full-thickness defects of the cornea and sclera. Equine pericardium preserved in glycerol was used to repair full-thickness corneal lesions after limbal melanoma excision and corneal wound with iris prolapse. A six-year old male, German Shepherd, with 1 cm of diameter, dark-pigmented mass at the temporal limbus of the right eye, with two months of evolution, and a four month old female mixed breed dog, with a corneal wound and iris prolapse, in the left eye, secondary to a cat scratch 5 days earlier. In both cases a piece of pericardium was sutured close to the corneal defects. An antibiotic ointment and atropine 1% eye drops were used. The intraocular pressure was low in the following days, but arose to normal values. All other structures were normal. A granulation tissue initially grew near the patch, and the opacity of the pericardium remained. Dexamethasone eye drops and ointment were used, and the granulation tissue disappeared two months after surgery. Eighteen months follow-up showed the eyes in good condition, although opaqueness was still present.

  4. Corneal biomechanical data and biometric parameters measured with Scheimpflug-based devices on normal corneas

    Science.gov (United States)

    Nemeth, Gabor; Szalai, Eszter; Hassan, Ziad; Lipecz, Agnes; Flasko, Zsuzsa; Modis, Laszlo

    2017-01-01

    AIM To analyze the correlations between ocular biomechanical and biometric data of the eye, measured by Scheimpflug-based devices on healthy subjects. METHODS Three consecutive measurements were carried out using the corneal visualization Scheimpflug technology (CorVis ST) device on healthy eyes and the 10 device-specific parameters were recorded. Pentacam HR-derived parameters (corneal curvature radii on the anterior and posterior surfaces; apical pachymetry; corneal volume; corneal aberration data; depth, volume and angle of the anterior chamber) and axial length (AL) from IOLMaster were correlated with the 10 specific CorVis ST parameters. RESULTS Measurements were conducted in 43 eyes of 43 volunteers (age 61.24±15.72y). The 10 specific CorVis ST data showed significant relationships with corneal curvature radii both on the anterior and posterior surface, pachymetric data, root mean square (RMS) data of lower-order aberrations, and posterior RMS of higher-order aberrations and spherical aberration of the posterior cornea. Anterior chamber depth showed a significant relationship, but there were no significant correlations between corneal volume, anterior chamber volume, mean chamber angle or AL and the 10 specific CorVis ST parameters. CONCLUSIONS CorVis ST-generated parameters are influenced by corneal curvature radii, some corneal RMS data, but corneal volume, anterior chamber volume, chamber angle and AL have no correlation with the biomechanical parameters. The parameters measured by CorVis ST seem to refer mostly to corneal properties of the eye. PMID:28251079

  5. Birefringence of the central cornea in children assessed with scanning laser polarimetry.

    Science.gov (United States)

    Irsch, Kristina; Shah, Ashesh A

    2012-08-01

    Corneal birefringence is a well-known confounding factor with all polarization-sensitive technology used for retinal scanning and other intraocular assessment. It has been studied extensively in adults, but little is known regarding age-related differences. Specifically, no information is available concerning corneal birefringence in children. For applications that are geared towards children, such as retinal birefringence scanning for strabismus screening purposes, it is important to know the expected range of both corneal retardance and azimuth in pediatric populations. This study investigated central corneal birefringence in children (ages three and above), by means of scanning laser polarimetry (GDx-VCC™, Carl Zeiss Meditec, Inc.). Children's measures of corneal retardance and azimuth were compared with those obtained in adults. As with previous studies in adults, corneal birefringence was found to vary widely in children, with corneal retardance ranging from 10 to 77 nm, and azimuth (slow axis) ranging from -11° to 71° (measured nasally downward). No significant differences in central corneal birefringence were found between children and adults, nor were significant age-related differences found in general. In conclusion, establishing knowledge of the polarization properties of the central cornea in children allows better understanding, exploitation, or bypassing of these effects in new polarization-sensitive pediatric ophthalmic applications.

  6. 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.

  7. Structure and function of the retinal pigment epithelium, photoreceptors and cornea in the eye of Sardinella aurita (Clupeidae, Teleostei

    Directory of Open Access Journals (Sweden)

    Mostafa Ali Salem

    2016-05-01

    Full Text Available The structure of the pigment epithelium, photoreceptors and the cornea in the eye of a teleost, Sardinella aurita was examined by light and electron microscopy. The retinal pigment epithelium forms a single layer of cells joined laterally by cell junctions. Centrally in the retina these cells are columnar, while more peripherally they become cuboidal in shape. The basal (scleral border of the pigment epithelial cells is not infolded but is relatively smooth. Phagosomes containing lysosome-like bodies are also common features of the retinal pigment epithelium. Numerous melanosomes (pigment granules are abundant throughout the epithelial cells. These melanosomes probably absorb light which has passed through the photoreceptor layer. Four photoreceptor cells were identified; rods, long single cones, short single cones and double cones. The presence of these types suggests a diversity of photoreceptor function. Square mosaic pattern of cones and well-developed choroid gland are also main features of the eye. The inner segment of rods and cones were rich in organelles indicating much synthetic activity. Calycal processes projecting from cone outer segments are also observed. The cornea includes an epithelium with a complex pattern of surface microplicae, a basement membrane, dermal stroma, an iridescent layer, scleral stroma, Descemet’s membrane and endothelium. The autochthonous layer which is seen in some teleosts has not been observed in the cornea of this species. These and other observations were discussed in relation to the photic environment and habits of this fish.

  8. Observation on ultrastructure and histopathology of cornea following femtosecond laser-assisted deep lamellar keratoplasty for acute corneal alkaline burns.

    Science.gov (United States)

    Li, Wen-Jing; Hu, Yu-Kun; Song, Hui; Gao, Xiao-Wei; Zhao, Xu-Dong; Dong, Jing; Guo, Yun-Lin; Cai, Yan

    2016-01-01

    To demonstrate the changes in ultrastructure and histopathology of the cornea in acute corneal alkaline burns after femtosecond laser-assisted deep lamellar keratoplasty. The New Zealand white rabbits treated with alkaline corneal burn were randomized into two groups, Group A (16 eyes) with femtosecond laser-assisted deep lamellar keratoplasty 24h after burn and Group B (16 eyes) without keratoplasty as controls. All eyes were evaluated with transmission electron microscopy (TEM) at 1, 2, 3, and 4wk follow-up, then all corneas were tested by hematoxylin and eosin staining histology. The corneal grafts in Group A were transparent, while those in Group B showed corneal stromal edema and loosely arranged collagen fibers. One week after treatment, TEM revealed the intercellular desmosomes in the epithelial layers and intact non-dissolving nuclei in Group A. At week 4, the center of the corneas in Group A was transparent with regularly arranged collagen fibers and fibroblasts in the stroma. In Group B, squamous cells were observed on the corneal surface and some epithelial cells were detached. Femtosecond laser-assisted deep lamellar keratoplasty can suppress inflammatory responses, prevent toxic substance-induced injury to the corneal endothelium and inner tissues with quicker recovery and better visual outcomes.

  9. 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.

  10. Richner-Hanhart syndrome (tyrosinemia type II). Case report and literature review.

    Science.gov (United States)

    al-Hemidan, A I; al-Hazzaa, S A

    1995-03-01

    Richner-Hanhart syndrome (Tyrosinemia Type II) is an autosomal recessive disorder of amino acid metabolism characterized by ocular changes, painful palmoplantar hyperkeratosis, and mental retardation. Serum tyrosine increases due to tyrosine aminotransferase deficiency resulting in the deposition of tyrosine crystals in the cornea and in corneal inflammation. Patients are often misdiagnosed as having herpes simplex keratitis. We report on a child who presented with bilateral keratitis secondary to Tyrosinemia Type II diagnosed as herpes simplex keratitis.

  11. Turkish population data on the short tandem repeat locus TPOX

    DEFF Research Database (Denmark)

    Vural, B; Poda, M; Atlioglu, E;

    1998-01-01

    Allele and genotype frequencies were determined for the STR (short tandem repeat) locus TPOX in a random Turkish population sample of 200 individuals.......Allele and genotype frequencies were determined for the STR (short tandem repeat) locus TPOX in a random Turkish population sample of 200 individuals....

  12. 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…

  13. Locus of Control, Attitudes toward Education, and Teaching Behaviors.

    Science.gov (United States)

    Kremer, Lya

    1982-01-01

    Tests 191 elementary school teachers in northern Israel for the relationships among locus of control, traditional and progressive educational attitudes, and related teaching behaviors. Finds external and internal locus of control explain the variance in traditional and progressive attitudes, respectively, and teaching behaviors. (Author/LC)

  14. The Cut Locus of a Torus of Revolution

    DEFF Research Database (Denmark)

    Gravesen, Jens; Markvorsen, Steen; Sinclair, Robert

    2005-01-01

    We determine the structure of the cut locus of a class of tori of revolution, which includes the standard tori in 3-dimensional Euclidean space.......We determine the structure of the cut locus of a class of tori of revolution, which includes the standard tori in 3-dimensional Euclidean space....

  15. 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

  16. Locus of Control and Protection of Consumer Rights

    Directory of Open Access Journals (Sweden)

    Ivan Krastev

    2012-10-01

    Full Text Available This paper examines the influence of locus of control on the consumer behavior. Theoretical supposition is proven by analyzing empirical data from a study of 287 students. The methods assessed the capacity for defending personal and consumer rights, as well as the type of locus of control.

  17. Locus of Control in Underachieving and Achieving Gifted Students.

    Science.gov (United States)

    McClelland, Robert; And Others

    1991-01-01

    This study, with 87 underachieving and 77 achieving gifted students in grades 6-9, found that general locus of control measures did not differentiate between the 2 groups, that both scored significantly higher on positive internal than on negative internal locus of control, and that there were no gender or grade effects. (Author/DB)

  18. Locus of Control and Marital Stability: A Longitudinal Study.

    Science.gov (United States)

    Constantine, John A.; Bahr, Stephen J.

    1980-01-01

    Investigated relationship between locus of control and marital stability of young men. Factors derived from locus of control measures included leadership, personal, and fate scales. Results indicated the only significant difference was on the leadership scale between men remaining married and those who did not. (RC)

  19. 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…

  20. 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.

  1. Locus of Control in Underachieving and Achieving Gifted Students.

    Science.gov (United States)

    McClelland, Robert; And Others

    1991-01-01

    This study, with 87 underachieving and 77 achieving gifted students in grades 6-9, found that general locus of control measures did not differentiate between the 2 groups, that both scored significantly higher on positive internal than on negative internal locus of control, and that there were no gender or grade effects. (Author/DB)

  2. 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…

  3. Sign Stability via Root Locus Analysis

    CERN Document Server

    Gibson, Travis E

    2015-01-01

    With the rise of network science old topics in ecology and economics are resurfacing. One such topic is structural stability (often referred to as qualitative stability or sign stability). A system is deemed structurally stable if the system remains stable for all possible parameter variations so long as the parameters do not change sign. This type of stability analysis is appealing when studying real systems as the underlying stability result only requires the scientist or engineer to know the sign of the parameters in the model and not the specific values. The necessary and sufficient conditions for qualitative stability however are opaque. In order to shed light on those conditions root locus analysis is employed. This technique allows us to illustrate the necessary conditions for qualitative stability.

  4. 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....... the lines of self-intersections of the front in the parametric space. This becomes possible by using the deformable simplicial complexes (DSC, [1]) method for deformable interface tracking. DSC provide a simple collision detection mechanism, allows for interface topology control, and does not require...

  5. 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.

  6. A short-term study of corneal collagen cross-linking with hypo-osmolar riboflavin solution in keratoconic corneas

    Institute of Scientific and Technical Information of China (English)

    Shao-Feng; Gu; Zhao-Shan; Fan; Li-Hua; Wang; Xiang-Chen; Tao; Yong; Zhang; Chun-Qin; Wang; Ya; Wang; Guo-Ying; Mu

    2015-01-01

    AIM: To report the 3mo outcomes of collagen crosslinking(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 to369.8 ±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.

  7. [Expression of matrix metalloproteinases and inhibitor on the cornea tissue in rabbit after implantation of modified titanium skirt for keratoprosthesis].

    Science.gov (United States)

    Li, Li; Zhou, Dilys; Wang, Xiu-mei; Wang, Xiao-ping; Cui, Fu-zhai; Lu, Yu-jie; Huang, Yi-fei

    2012-01-01

    To investigate the expression of matrix metalloproteinase-2 (MMP-2) and Tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in rabbit corneas implanted with modified titanium skirt of keratoprosthesis in order to explore the potential roles. A total of 20 New Zealand white rabbits with corneal alkali burn in right eye rabbit corneas were divided into three groups. There were 6 animals in each group. Skirt of hydroxyapatite/Sandblast-Titanium and Sandblast-Titanium were inserted into the corneal stroma of rabbits in group A and group B. The group C did not insert skirt as surgical control.2 rabbits were as normal control D group. A total of 20 New Zealand white rabbits were divided into four groups with the same way. The expression of MMP-2 and TIMP-2 was determined by immunohistochemistry at 1 month, 3 months. The expression of MMP-2 and TIMP-2 mRNA level was determined by real time-polymerase chain reaction, and its protein level was determined by western blot. The optical cylinder was implanted to rabbit corneas, which were implanted with modified titanium skirt after 3 months. There was one case of corneal dissolution being found in group F. MMP-2 and TIMP-2 immunoreactivities were expressed in the normal corneas, predominantly in the corneal epithelium. After injury, immunoreactivities of both MMP-2 and TIMP-2 were increased notably in the healing corneal epithelium, infiltrating inflammatory cells, stromal fibroblasts and in growing vascular endothelial cells. The expression of MMP-2 was lower in group A and E than that in group B and F after 1 month and 3 months (t = 12.05, 2.93, 12.006, 3.781, P 0.05); MMP-2 immunoreactivities were absent or lowly expressed predominantly in the corneal epithelium of normal corneas. The expression of MMP-2, TIMP-2 mRNA level was parallel that of protein level. The expression of MMP-2 was lower in the corneal tissue sections of HA/SB-Ti skirt inserted eyes than that in the tissue sections of SB-Ti skirt inserted eyes. The

  8. A study of the TNF/LTA/LTB locus and susceptibility to severe malaria in highland papuan children and adults

    Directory of Open Access Journals (Sweden)

    Granger Donald L

    2010-10-01

    Full Text Available Abstract Background Severe malaria (SM syndromes caused by Plasmodium falciparum infection result in major morbidity and mortality each year. However, only a fraction of P. falciparum infections develop into SM, implicating host genetic factors as important determinants of disease outcome. Previous studies indicate that tumour necrosis factor (TNF and lymphotoxin alpha (LTα may be important for the development of cerebral malaria (CM and other SM syndromes. Methods An extensive analysis was conducted of single nucleotide polymorphisms (SNPs in the TNF, LTA and LTB genes in highland Papuan children and adults, a population historically unexposed to malaria that has migrated to a malaria endemic region. Generated P-values for SNPs spanning the LTA/TNF/LTB locus were corrected for multiple testing of all the SNPs and haplotype blocks within the region tested through 10,000 permutations. A global P-value of Results No associations between SNPs in the TNF/LTA/LTB locus and susceptibility to SM in highland Papuan children and adults were found. Conclusions These results support the notion that unique selective pressure on the TNF/LTA/LTB locus in different populations has influenced the contribution of the gene products from this region to SM susceptibility.

  9. Effects of preferred retinal locus placement on text navigation and development of advantageous trained retinal locus.

    Science.gov (United States)

    Watson, Gale R; Schuchard, Ronald A; De l'Aune, William R; Watkins, Erica

    2006-01-01

    Sixty readers were evaluated for visual function and text-navigation ability. The visual field and preferred retinal locus (PRL) were measured with a scanning laser ophthalmoscope (SLO). We found significant differences in text-navigation ability based on scotoma and PRL placement. Readers with a PRL to the left of or above a scotoma had significantly less text-navigation abilities. Readers with a PRL to the left of a scotoma tended to misread words with similar beginnings and omit the last word on a line. Readers with a PRL above a scotoma tended to skip a line or reread the same line twice. In a follow-up study, seven subjects with a nonadvantageous PRL quickly developed a trained retinal locus (TRL) during instruction with an SLO. Although the readers developed the TRL in about 15 minutes, they read slower with the TRL than the PRL. This TRL research provides promising pilot data.

  10. 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

  11. Cohen Syndrome. A Case Report

    Directory of Open Access Journals (Sweden)

    Elayne Esther Santana Hernández

    2014-04-01

    Full Text Available Cohen syndrome is a rare genetic disease that is transmitted in an autosomal recessive pattern. It is characterized by obesity, hypotonia, mental retardation, microcephaly, typical craniofacial dysmorphism, large and prominent central incisors as well as thin, spindle-shaped fingers. The locus for Cohen syndrome has been located on chromosome 8q 22 (COH 1. Few cases have been reported since its description, it is clinically diagnosed through a proper delineation of the phenotype. The case of 14-year-old patient with this syndrome in whom a clinical diagnosis had not been established thus far is presented. An accurate delineation of the phenotype was achieved at this age and consequently, the correct diagnosis was reached, which is critical in order to provide better genetic counseling to the family.

  12. Effect of topical fluoroquinolones on the expression of matrix metalloproteinases in the cornea

    Directory of Open Access Journals (Sweden)

    O'Brien Terrence P

    2003-10-01

    Full Text Available Abstract Background Matrix metalloproteinases play an important role in extracellular matrix deposition and degradation. Based on previous clinical observations of corneal perforations during topical fluoroquinolone treatment, we decided to evaluate the comparative effects of various fluoroquinolone eye drops on the expression of matrix metalloproteinases (MMPs in cornea. Methods Eighty female Lewis rats were divided into two experimental groups: intact and wounded corneal epithelium. Uniform corneal epithelial defects were created in the right eye with application of 75% alcohol in the center of the tissue for 6 seconds. The treatment groups were tested as follows: 1 Tear drops: carboxymethylcellulose sodium 0.5 % (Refresh, Allergan; 2 Ciprofloxacin 0.3% (Ciloxan, Alcon; 3 Ofloxacin 0.3%(Ocuflox, Allergan; 4 Levofloxacin 0.5%(Quixin, Santen. Eye drops were administered 6 times a day for 48 hours. Rats were sacrificed at 48 hours. Immunohistochemical analysis and zymography were conducted using antibodies specific to MMPs-1, 2, 8 and 9. Results MMP-1, MMP-2, MMP-8 and MMP-9 expression were detected at 48 hrs in undebrided corneal epithelium groups treated with the topical fluoroquinolones. No statistical difference was observed in quantitative expression of MMPs among ciprofloxacin 0.3%, ofloxacin 0.3%, levofloxacin 0.5%. When the artificial tear group and the fluoroquinolone groups with corneal epithelial defect were compared, increased expression of MMPs was observed as a result of the wound healing process. However, the fluoroquinolone treated group exhibited high statistically significantly levels of MMPs expression. Conclusions Our study provides preliminary evidence that topical application of fluoroquinolone drugs can induce the expression of MMP-1, MMP-2, MMP-8 and MMP-9 in the undebrided corneal epithelium compared to artificial tear eye drops.

  13. Antinociceptive and anti-inflammatory activities of sulphated polysaccharides from the red seaweed Gracilaria cornea.

    Science.gov (United States)

    Coura, Chistiane O; de Araújo, Ianna W F; Vanderlei, Edfranck S O; Rodrigues, José A G; Quinderé, Ana L G; Fontes, Bruno P; de Queiroz, Ismael N L; de Menezes, Dalgimar B; Bezerra, Mirna M; e Silva, Antonio A R; Chaves, Hellíada V; Jorge, Roberta J B; Evangelista, Janaina S A M; Benevides, Norma M B

    2012-04-01

    Seaweeds have attracted special interest as good sources of sulphated polysaccharides (SP) for use in pharmaceutical industries and biotechnology. In this study, we evaluated the effects of SP from the red seaweed Gracilaria cornea (Gc-TSP) in nociceptive and inflammatory models. In mice, Gc-TSP (3, 9 or 27 mg/kg) significantly reduced nociceptive responses, as measured by the number of writhes, at all tested doses. In a formalin test, Gc-TSP significantly reduced licking time in both phases of the test at a dose of 27 mg/kg. In a hot-plate test, the antinociceptive effect was observed only in animals treated with 27 mg/kg of Gc-TSP, suggesting that the analgesic effect occurs through a central action mechanism at the highest dose. Gc-TSP (3, 9 or 27 mg/kg) caused only a slight reduction in neutrophil migration in the rat peritoneal cavity. However, lower doses of Gc-TSP (3 and 9 mg/kg) significantly inhibited paw oedema induced by carrageenan, especially at 3 hr after treatment. Reduction in oedema was confirmed by myeloperoxidase activity in the affected paw tissue. In addition, treatment (s.c.) of animals with different doses of Gc-TSP inhibited paw oedema induced by dextran within the first hour in all doses tested. After 14 consecutive days of intraperitoneal administration of Gc-TSP (9 mg/kg), we measured the wet weight of the liver, kidney, heart, spleen and thymus and performed biochemical, haematological and histopathological evaluations. No systemic damage was found. These results indicate that Gc-TSP possesses analgesic and anti-inflammatory effects and is a potentially important tool worthy of further study.

  14. Visual pigments, oil droplets, lens, and cornea characterization in the whooping crane (Grus americana)

    Science.gov (United States)

    Porter, Megan L.; Kingston, Alexandra C. N.; McCready, Robert; Cameron, Evan G.; Hofmann, Christopher M.; Suarez, Lauren; Olsen, Glenn H.; Cronin, Thomas W.; Robinson, Phyllis R.

    2014-01-01

    Vision has been investigated in many species of birds, but few studies have considered the visual systems of large birds and the particular implications of large eyes and long-life spans on visual system capabilities. To address these issues we investigated the visual system of the whooping crane, Grus americana (Gruiformes: Gruidae). G. americana (an endangered species) is one of only two North American crane species and represents a large, long-lived bird where ultraviolet sensitivity may be degraded by chromatic aberrations and entrance of ultraviolet light into the eye could be detrimental to retinal tissues. To investigate the whooping crane visual system we used microspectrophotometry to determine the absorbance spectra of retinal oil droplets and to investigate if the ocular media (i.e., the lens and cornea) absorbs UV light. In vitro expression and reconstitution was used to determine the absorbance spectra of rod and cone visual pigments. The rod visual pigments had wavelengths of peak absorbance (λmax) at 500 nm, while the cone visual pigments λmax values were determined to be 404 nm (SWS1), 450 nm (SWS2), 499 nm (RH2), and 561 nm (LWS), similar to other characterized bird visual pigment absorbance values. The oil droplet cutoff wavelength (λcut) values similarly fell within ranges recorded from other avian species: 576 nm (R-type), 522 nm (Y-type), 506 nm (P-type), and 448 nm (C-type). We confirm that G. americana has a violet-sensitive visual system, although based on the λmax of the SWS1 visual pigment (404 nm) may also have some ability for UV sensitivity.

  15. [The effects of ocular hypotensive drugs on the cornea: an in vivo analysis with confocal microscopy].

    Science.gov (United States)

    Fernández Jiménez-Ortiz, H; Toledano Fernández, N; Fernández Escamez, C S; Perucho Martinez, S; Crespo Carballés, M J

    2013-11-01

    To evaluate the effects of anti-glaucoma treatments containing benzalconium chloride (BAC) on the human cornea. A prospective single masked cohort study was conducted on the 50 eyes of 50 patients. The inclusion criteria were: recently diagnosed glaucoma or ocular hypertension with previous treatment, or ophthalmologist-prescribed anti-glaucoma therapy, and oral consent to participate in the study. The patients were not randomised, as the ophthalmologist decided the best therapy according to clinical criteria. The patients were divided in 2 cohorts: one exposed to BAC (23 patients), and not exposed (27 patients). The mean follow-up period was 22 weeks (range 18-30). The change in cell density before and after therapy was measured in: basal layer epithelium, basal layer of limbal epithelium and endothelium. The change in stromal reflectivity and the number of nerve branches in sub-basal nerve plexus was also measured. BAC exposure was blinded to the main researcher. A greater increase in basal layer epithelium cell density was observed in BAC exposed cohort (P<.05). No significant differences were detected in the endothelium, limbal cell density, stromal reflectivity, or sub-basal nerve plexus. Age, sex, IOP, active ingredient or BAC concentration did not affect the direction or magnitude of the ocular surface alterations found. Chronic anti-glaucoma therapy induces changes in the corneal epithelium. Preservative free drops showed less disruption of the ocular surface by confocal microscopy analysis. Further studies should be conducted to evaluate the clinical impact of these histological findings. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  16. 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.

  17. Rebamipide increases the amount of mucin-like substances on the conjunctiva and cornea in the N-acetylcysteine-treated in vivo model.

    Science.gov (United States)

    Urashima, Hiroki; Okamoto, Takashi; Takeji, Yasuhiro; Shinohara, Hisashi; Fujisawa, Shigeki

    2004-08-01

    Rebamipide increases the amount of mucin-like substances in the stomach. We aimed to determine the effects of rebamipide on the amount of mucin-like substances in the conjunctiva and cornea of N-acetylcysteine-treated eyes. Furthermore, we attempted to evaluate the effects of rebamipide on the wound healing of N-acetylcysteine-treated eyes. The model was created by instilling 10% N-acetylcysteine solutions into rabbit eyes. Rebamipide was then applied on the day following the completion of N-acetylcysteine treatment. The amount of mucin-like substances on the conjunctiva and cornea was measured using the Alcian-blue binding method. The degree of damage was evaluated using scores based on the areas and densities of the cornea and conjunctival after staining using a rose Bengal solution under blind conditions. Rebamipide increased the level of mucin-like substances on the conjunctiva of N-acetylcysteine-treated eyes when instilled at concentrations of 0.3% or higher, and 1% rebamipide increased the amount of mucin-like substances covering the cornea. Moreover, 1% rebamipide improved the rose Bengal scores of the cornea and conjunctiva in N-acetylcysteine-treated eyes. Rebamipide increased mucin-like substances on the cornea and conjunctiva of N-acetylcysteine-treated eyes. In accordance with the mucin-increasing effects, rebamipide improved the rose Bengal scores for the cornea and conjunctiva of N-acetylcysteine-treated eyes. However, the relevance of these findings to dry eyes is unclear because it is not known whether the change in mucus expression in the N-acetylcysteine model is similar to what occurs in aqueous tear deficiency. Consequently, it may be worth trying on an animal model of keratoconjunctivitis sicca.

  18. Low Cost Upper Atmosphere Sounder (LOCUS)

    Science.gov (United States)

    Gerber, Daniel; Swinyard, Bruce M.; Ellison, Brian N.; Aylward, Alan D.; Aruliah, Anasuya; Plane, John M. C.; Feng, Wuhu; Saunders, Christopher; Friend, Jonathan; Bird, Rachel; Linfield, Edmund H.; Davies, A. Giles; Parkes, Steve

    2014-05-01

    near future. We describe the current instrument configuration of LOCUS, and give a first preview of the expected science return such a mission would yield. The LOCUS instrument concept calls for four spectral bands, a first band at 4.7 THz to target atomic oxygen (O), a second band at 3.5 THz to target hydroxyl (OH), a third band at 1.1 THz to cover several diatomic species (NO, CO, O3, H2O) and finally a fourth band at 0.8 THz to retrieve pointing information from molecular oxygen (O2). LOCUS would be the first satellite instrument to measure atomic oxygen on a global scale with a precision that will allow the retrieval of the global O distribution. It would also be the first time that annual and diurnal changes in O are measured. This will be a significant step forward in understanding the chemistry and dynamics of the MLT. Current indications (derived from CRISTA measurement) lead us to believe that current models only give a poor representation of upper atmospheric O. The secondary target species can help us to address additional scientific questions related to both Climate (distribution of climate relevant gases, highly geared cooling of the MLT in response to Climate change, increased occurrence of Polar Mesospheric Clouds (PMC), etc) and Space Weather (precipitation of electrically charged particles and impact on NOx chemistry, fluctuations of solar Lyman-alpha flux through shown in the the distribution of photochemically active species, etc).

  19. 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

  20. Germline mosaicism at the fragile X locus.

    Science.gov (United States)

    Prior, T W; Papp, A C; Snyder, P J; Sedra, M S; Guida, M; Enrile, B G

    1995-01-30

    We have identified a fragile X syndrome pedigree where the disorder is associated with a molecular deletion. The deletion was present in the DNA of 2 sons but was absent in the mother's somatic cell (lymphocyte) DNA. The results are consistent with the deletion arising as a postzygotic event in the mother, who therefore is germinally mosaic. This finding has important implications for counseling fragile X families with deletion mutations.

  1. 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

  2. Expression at the imprinted dlk1-gtl2 locus is regulated by proneural genes in the developing telencephalon.

    Directory of Open Access Journals (Sweden)

    Julie Seibt

    Full Text Available Imprinting is an epigenetic mechanism that restrains the expression of about 100 genes to one allele depending on its parental origin. Several imprinted genes are implicated in neurodevelopmental brain disorders, such as autism, Angelman, and Prader-Willi syndromes. However, how expression of these imprinted genes is regulated during neural development is poorly understood. Here, using single and double KO animals for the transcription factors Neurogenin2 (Ngn2 and Achaete-scute homolog 1 (Ascl1, we found that the expression of a specific subset of imprinted genes is controlled by these proneural genes. Using in situ hybridization and quantitative PCR, we determined that five imprinted transcripts situated at the Dlk1-Gtl2 locus (Dlk1, Gtl2, Mirg, Rian, Rtl1 are upregulated in the dorsal telencephalon of Ngn2 KO mice. This suggests that Ngn2 influences the expression of the entire Dlk1-Gtl2 locus, independently of the parental origin of the transcripts. Interestingly 14 other imprinted genes situated at other imprinted loci were not affected by the loss of Ngn2. Finally, using Ngn2/Ascl1 double KO mice, we show that the upregulation of genes at the Dlk1-Gtl2 locus in Ngn2 KO animals requires a functional copy of Ascl1. Our data suggest a complex interplay between proneural genes in the developing forebrain that control the level of expression at the imprinted Dlk1-Gtl2 locus (but not of other imprinted genes. This raises the possibility that the transcripts of this selective locus participate in the biological effects of proneural genes in the developing telencephalon.

  3. Metabolic Syndrome

    Science.gov (United States)

    ... hypertension, hypertriglyceridemia, insulin resistance syndrome, low HDL cholesterol, Metabolic Syndrome, overweight, syndrome x, type 2 diabetes Family Health, Kids and Teens, Men, Women January 2005 Copyright © American Academy of Family PhysiciansThis ...

  4. Marfan Syndrome

    Science.gov (United States)

    Marfan syndrome is a disorder that affects connective tissue. Connective tissues are proteins that support skin, bones, ... fibrillin. A problem with the fibrillin gene causes Marfan syndrome. Marfan syndrome can be mild to severe, ...

  5. Williams syndrome

    Science.gov (United States)

    Williams-Beuren syndrome ... Williams syndrome is caused by not having a copy of several genes. Parents may not have any family history of the condition. However, people with Williams syndrome have a 50% chance of passing the ...

  6. Fahr's Syndrome

    Science.gov (United States)

    ... Page You are here Home » Disorders » All Disorders Fahr's Syndrome Information Page Fahr's Syndrome Information Page What research is being done? ... and conducts research on neurogenetic disorders such as Fahr's Syndrome. The goals of this research are to ...

  7. Localization of angiotensin converting enzyme in rabbit cornea and its role in controlling corneal angiogenesis in vivo.

    Science.gov (United States)

    Sharma, Ajay; Bettis, Daniel I; Cowden, John W; Mohan, Rajiv R

    2010-04-23

    The renin angiotensin system (RAS) has been shown to modulate vascular endothelial growth factor and angiogenesis. In this study we investigated (i) the existence of the RAS components angiotensin converting enzyme (ACE) and angiotensin II receptors (AT(1) and AT(2)) in the rabbit cornea using in vitro and ex vivo models and (ii) the effect of enalapril, an ACE inhibitor, to inhibit angiogenesis in rabbit cornea in vivo. New Zealand White rabbits were used. Cultured corneal fibroblasts and corneal epithelial cells were used for RNA isolation and cDNA preparation using standard molecular biology techniques. PCR was performed to detect the presence of ACE, AT(1), and AT(2) gene expression. A corneal micropocket assay to implant a vascular endothelial growth factor (VEGF) pellet in the rabbit cornea was used to induce corneal angiogenesis. Rabbits of the control group received sterile water, and the treated group received 3 mg/kg enalapril intramuscularly once daily for 14 days starting from day 1 of pellet implantation. The clinical eye examination was performed by slit-lamp biomicroscopy. We monitored the level of corneal angiogenesis in live animals by stereomicroscopy at days 4, 9, and 14 after VEGF pellet implantation. Collagen type IV and lectin immunohistochemistry and fluorescent microscopy were used to measure corneal angiogenesis in tissue sections of control and enalapril-treated corneas of the rabbits. Image J software was used to quantify corneal angiogenesis in the rabbit eye in situ. Our data demonstrated the presence of ACE, AT(1), and AT(2) expression in corneal fibroblasts. Cells of corneal epithelium expressed AT(1) and AT(2) but did not show ACE expression. Slit-lamp examination did not show any significant difference between the degree of edema or cellular infiltration between the corneas of control and enalapril-treated rabbits. VEGF pellet implantation caused corneal angiogenesis in the eyes of vehicle-treated control rabbits, and the mean area

  8. Locus of control and cerebral asymmetry.

    Science.gov (United States)

    De Brabander, B; Boone, C; Gerits, P

    1992-08-01

    Data about the lack of synchronism of flexor carpi ulnaris peak EMG values of bimanual reactions during a semantic and during a visuospatial discrimination reaction time task are reported. The effects of type of task as well as the presence or absence of an unexpected stimulus preceding the reaction stimulus on lack of synchronism clearly depend upon the locus of control of the subjects, as measured on Rotter's I-E scale. On the basis of several arguments it is proposed that the measure of lack of synchronism reflects in an opposite sense the amount of dopaminergic activation or motor readiness in the sense in which Pribram and McGuinness in 1975 and Tucker and Williamson in 1984 have defined these concepts. The results for 15 women and 18 men show that more internally oriented subjects are more activated by a semantic task and by an unexpected preparatory stimulus in this type of task than more externally oriented subjects. The opposite appears to hold on the visuospatial task and unexpected preparatory stimuli therein. Together with earlier findings about reaction times and a number of relevant findings in the literature, the results are interpreted as indicative of basic differences in asymmetric tonic activation of the cerebral hemispheres between more internally and more externally oriented subjects. A model is proposed to explain phasic activating effects which ensue when tonically more left- or right-activated subjects perform left- or right-hemisphere tasks and when supplementary irrelevant stimuli are received.

  9. THE LOCUS COERULEUS AND CENTRAL CHEMOSENSITIVITY

    Science.gov (United States)

    Gargaglioni, Luciane H.; Hartzler, Lynn K.; Putnam, Robert W.

    2010-01-01

    The locus coeruleus (LC) lies in the dorsal pons and supplies noradrenergic (NA) input to many regions of the brain, including respiratory control areas. The LC may provide tonic input for basal respiratory drive and is involved in central chemosensitivity since focal acidosis of the region stimulates ventilation and ablation reduces CO2-induced increased ventilation. The output of LC is modulated by both serotonergic and glutamatergic inputs. A large percentage of LC neurons are intrinsically activated by hypercapnia. This percentage and the magnitude of their response are highest in young neonates and decrease dramatically after postnatal day P10. The cellular bases for intrinsic chemosensitivity of LC neurons are comprised of multiple factors, primary among them being reduced extracellular and intracellular pH, which inhibit inwardly rectifying and voltage-gated K+ channels, and activate L-type Ca2+ channels. Activation of KCa channels in LC neurons may limit their ultimate response to hypercapnia. Finally, the LC mediates central chemosensitivity and contains pH-sensitive neurons in amphibians, suggesting that the LC has a long-standing phylogenetic role in respiratory control. PMID:20435170

  10. Artificial cornea: surface modification of silicone rubber membrane by graft polymerization of pHEMA via glow discharge.

    Science.gov (United States)

    Lee, S D; Hsiue, G H; Kao, C Y; Chang, P C

    1996-03-01

    A method for producing various surfaces of silicone rubber membrane (SR) was developed in this study by grafting various amounts of poly(2-hydroxy ethyl methacrylate) (pHEMA) onto SR by plasma-induced grafted polymerization (PIP) as a homobifunctional membrane. The elemental composition and different carbon bindings on the surface of SR were examined by electron spectroscopy for chemical analysis with the amount of O1s/C1s being approximately 0.7 at 1 min, 60 W, 200 mTorr of Ar-plasma treatment. The peroxide group introduced on SR was measured via 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the amount of 6.85 x 10(-8) mol cm-2 reached optimum value at 1 min of Ar-plasma treatment. After Ar-plasma treated SR, the peroxide group (33D peak) was introduced on the surface of SR by negative spectra of secondary ion mass spectroscopy analysis, whereas ester groups (72D peak) were observed for pHEMA-grafted SR. For the in vitro test, the influence of various surfaces of SR on attachment and growth of rabbit corneal epithelial cells (CEC) was studied by cell culture assay. These results indicated that 56-150 micrograms cm-2 of pHEMA grafted onto SR were suitable values for attachment and growth of CEC. On the contrary, the large grafted amounts (500-1650 micrograms cm-2) of pHEMA on SR were insufficient for attachment and growth of CEC. For the in vivo test, the migration of CEC from host cornea to implant was investigated by slit lamp microscopy. The experimental results indicated that SRs grafted with pHEMA were completely covered with CEC 3 weeks after implantation of the membranes into the host cornea. These results provide a valuable reference for developing an artificial cornea.

  11. Noninvasive measurement of wave speed of porcine cornea in ex vivo porcine eyes for various intraocular pressures.

    Science.gov (United States)

    Zhou, Boran; Sit, Arthur J; Zhang, Xiaoming

    2017-11-01

    The objective of this study was to extend an ultrasound surface wave elastography (USWE) technique for noninvasive measurement of ocular tissue elastic properties. In particular, we aim to establish the relationship between the wave speed of cornea and the intraocular pressure (IOP). Normal ranges of IOP are between 12 and 22mmHg. Ex vivo porcine eye balls were used in this research. The porcine eye ball was supported by the gelatin phantom in a testing container. Some water was pour into the container for the ultrasound measurement. A local harmonic vibration was generated on the side of the eye ball. An ultrasound probe was used to measure the wave propagation in the cornea noninvasively. A 25 gauge butterfly needle was inserted into the vitreous humor of the eye ball under the ultrasound imaging guidance. The needle was connected to a syringe. The IOP was obtained by the water height difference between the water level in the syringe and the water level in the testing container. The IOP was adjusted between 5mmHg and 30mmHg with a 5mmHg interval. The wave speed was measured at each IOP for three frequencies of 100, 150 and 200Hz. Finite element method (FEM) was used to simulate the wave propagation in the corneal according to our experimental setup. A linear viscoelastic FEM model was used to compare the experimental data. Both the experiments and the FEM analyses showed that the wave speed of cornea increased with IOP. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. 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.

  13. Innervation of TRPV1-, PGP-, and CGRP-immunoreactive nerve fibers in the subepithelial layer of a whole mount preparation of the rat cornea.

    Science.gov (United States)

    Hiura, Akio; Nakagawa, Hiroshi

    2012-01-01

    The pattern of innervation of capsaicin receptor, TRPV1-(transient receptor protein vanilloid 1), PGP 9.5-(protein gene product, a marker of peripheral nerve fibers)-, and CGRP (calcitonin gene-related peptide)-immunoreactive (IR) nerve fibers was examined by immunohistological staining of whole mount preparations of the adult rat cornea. The outer corneoscleral limbus toward the central cornea in the subepithelial (stromal) layer was richly innervated by a meshwork of PGP- and CGRP-IR nerve fibers. Sparse innervation was observed in the central cornea, presumably owing to insufficient staining. Dense innervation of TRPV1-IR nerve fibers were demonstrated in addition to innervation of PGP- and CGRP-IR nerve fibers, running from the corneoscleral margin to the central cornea. Although the density of TRPV1-IR nerve fibers appeared to gradually diminish, immunostaining of TRPV1-IR nerve fibers was not as clear as that of PGP- and CGRP-IR nerve fibers. The TRPV1-IR nerve fibers appeared to be thinner than the PGP- and CGRP-IR nerve fibers. The TRPV1-IR leash fibers were observed in the basal epithelial layer, presumably ensuring effective corneal reflex, response to noxious stimuli, and repair of cornea injury.

  14. Lymphatic vessels growing apart from blood vessels in transplanted corneas after the blockade of vascular endothelial growth factor C

    Institute of Scientific and Technical Information of China (English)

    Ye Hui; Yan Hao; Zhong Lei; Wang Tao; Deng Juan; Ling Shi-qi

    2016-01-01

    BACKGROUND:Corneal lymphangiogenesis is beneficial to the transport of corneal antigenic materials, and accelerates the process of antigen presentation, thereby playing an important role in corneal immunity. However, due to the paral el outgrowth of corneal blood and lymphatic vessels in transplanted corneas, it is often difficult to accurately evaluate the role of corneal lymphatic vessels in allograft rejection. OBJECTIVE:To explore the development of corneal lymphangiogenesis and angiogenesis in transplanted rat corneas after the blockade of vascular endothelial growth factor C (VEGF-C). METHODS:130 rats used to establish corneal al ogenic transplantation models were equally randomized into two groups:the anti-VEGF-C group and the control group. VEGF-C was blocked in the anti-VEGF-C group by intraperitoneal injection of neutralizing monoclonal anti-VEGF-C antibody every other day for 2 consecutive weeks. Meanwhile, rats in control groups received intraperitoneal injections of saline. Corneal angiogenesis and lymphangiogenesis were characterized using whole mount immunofluorescence, and the immune rejection of the grafts was evaluated by scoring the rejection index (RI). In addition, the expression of VEGF-C was examined by real-time PCR. The relationship of corneal lymphangiogenesis and angiogenesis to RI in transplanted corneas was also characterized. RESULTS AND CONCLUSION:VEGF-C expression was markedly downregulated after VEGF-C blockade. Corneal lymphangiogenesis developed in parallel with corneal angiogenesis in the control group. While there was a mild reduction in blood vessel area (BVA) and a significant decrease in lymphatic vessel area (LVA) in the anti-VEGF-C group (P0.05). the graft survival time in the anti-VEGF-C group was significantly increased compared with that in the control group (P<0.05). Our results show that the outgrowth of lymphatic vessels is separated from that of blood vessels in transplanted corneas by blocking VEGF-C. The blockade

  15. 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.

  16. Change in over-refraction after scleral lens settling on average corneas.

    Science.gov (United States)

    Bray, Chelsea; Britton, Stephanie; Yeung, Debby; Haines, Lacey; Sorbara, Luigina

    2017-07-01

    The purpose of this study was to determine the change in over-refraction, if any, after a scleral lens settled on the eye for 6-8 h. Sixteen patients of varying refractive errors and normal corneal curvatures (measured with Pentacam(™) Oculus) were fitted with trial Mini-Scleral Design (MSD) scleral lenses (15.8 mm diameter) in one eye. The sagittal depths of the scleral lenses were selected by adding 350 μm to the corneal sagittal heights measured at a chord length of 15 mm with the Visante(™) optical coherence tomographer (OCT) anterior segment scans and picking the closest available trial lens in the set. Initial measurements were taken 30 min after lens insertion and included an auto-refraction, subjective refraction, and best sphere refraction over the contact lens. Visual acuities and Visante(™) OCT anterior segment scans were also taken. These measurements were repeated after 6-8 h of lens wear. Over the trial wearing period, the average change in the spherical component of the over-refraction was +0.06 D (S.D. 0.17) (p = 0.16). The average change in cylinder was +0.04 D (S.D. 0.19) (p = 0.33). The average absolute change in axis was 1.06° (S.D. 12.11) (p = 0.74). The average change in best sphere was +0.13 ± 0.30 D (p = 0.12). There was no significant change in visual acuity with the best sphere over-refraction over the 6-8 h wearing period. There was a significant change in central corneal clearance over the wearing period of 83 μm (S.D. 22) (p refraction (sphere, cylinder, and axis) or best sphere or visual acuity. This study has confirmed that there is no link between reduction in central corneal clearance and change in over-refraction for average corneas. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

  17. Phage display against corneal epithelial cells produced bioactive peptides that inhibit Aspergillus adhesion to the corneas.

    Directory of Open Access Journals (Sweden)

    Ge Zhao

    Full Text Available Dissection of host-pathogen interactions is important for both understanding the pathogenesis of infectious diseases and developing therapeutics for the infectious diseases like various infectious keratitis. To enhance the knowledge about pathogenesis infectious keratitis, a random 12-mer peptide phage display library was screened against cultured human corneal epithelial cells (HCEC. Fourteen sequences were obtained and BLASTp analysis showed that most of their homologue counterparts in GenBank were for defined or putative proteins in various pathogens. Based on known or predicted functions of the homologue proteins, ten synthetic peptides (Pc-A to Pc-J were measured for their affinity to bind cells and their potential efficacy to interfere with pathogen adhesion to the cells. Besides binding to HCEC, most of them also bound to human corneal stromal cells and umbilical endothelial cells to different extents. When added to HCEC culture, the peptides induced expression of MyD88 and IL-17 in HCEC, and the stimulated cell culture medium showed fungicidal potency to various extents. While peptides Pc-C and Pc-E inhibited Aspergillus fumigatus (A.f adhesion to HCEC in a dose-dependent manner, the similar inhibition ability of peptides Pc-A and Pc-B required presence of their homologue ligand Alb1p on A.f. When utilized in an eyeball organ culture model and an in vivo A.f keratitis model established in mouse, Pc-C and Pc-E inhibited fungal adhesion to corneas, hence decreased corneal disruption caused by inflammatory infiltration. Affinity pull-down of HCEC membrane proteins with peptide Pc-C revealed several molecules as potential receptors for this peptide. In conclusion, besides proving that phage display-selected peptides could be utilized to interfere with adhesion of pathogens to host cells, hence could be exploited for managing infectious diseases including infectious keratitis, we also proposed that the phage display technique and the

  18. 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

  19. automatic generation of root locus plots for linear time invariant ...

    African Journals Online (AJOL)

    user

    root locus as a time domain technique for system design and analysis. The Tool Box can also ... theory, it has equally been applied to classical formulation and the ... major constraint, therefore the use of complex graphical ..... The computation.

  20. Y-Chromosome short tandem repeat, typing technology, locus ...

    African Journals Online (AJOL)

    Aghomotsegin

    technology, locus information and allele frequency in different ... DNA can be used to study human evolution. Besides ... STR markers are important for human identification ..... discovery resource for research on human genetic variation.

  1. 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

  2. Evidence of a locus for orofacial clefting on human chromosome 6p24 and STS content map of the region.

    Science.gov (United States)

    Davies, A F; Stephens, R J; Olavesen, M G; Heather, L; Dixon, M J; Magee, A; Flinter, F; Ragoussis, J

    1995-01-01

    Orofacial clefting is genetically complex, no single gene being responsible for all forms. It can, however, result from a single gene defect either as part of a syndrome (e.g. van der Woude syndrome, Treacher-Collins syndrome, velo-cardio-facial syndrome) or as an isolated phenotypic effect (e.g. X-linked cleft palate; non-syndromic, autosomal dominant orofacial clefting). Several studies have suggested that chromosome 6p is a candidate region for a locus involved in orofacial clefting. We have used YAC clones from contigs in 6p25-p23 to investigate three unrelated cases of cleft lip and palate coincident with chromosome 6p abnormalities. Case 1 has bilateral cleft lip and palate and a balanced translocation reported as 46,XY,t(6,7)(p23;q36.1). Case 2 has multiple abnormalities including cleft lip and palate and was reported as 46,XX,del(6)(p23;pter). Case 3 has bilateral cleft lip and palate and carries a balanced translocation reported as 46,XX,t(6;9)(p23;q22.3). We have identified two YAC clones, both of which cross the breakpoint in cases 1 and 3 and are deleted in case 2. These clones map to 6p24.3 and therefore suggest the presence of a locus for orofacial clefting in this region. The HGP22 and AP2 genes, potentially involved in face formation, have been found to flank this region, while F13A maps further telomeric in 6p24.3/25.

  3. Clinical and molecular phenotype of Aicardi-Goutieres syndrome

    DEFF Research Database (Denmark)

    Rice, Gillian; Patrick, Teresa; Parmar, Rekha

    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. 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-Juergen; 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.; Gueet, 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-Buergi, 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 comple

  5. DOWN SYNDROME WITH MOYAMOYA SYNDROME

    National Research Council Canada - National Science Library

    Mohan Makwana; R. K. Vishnoi; Jai Prakash Soni; Kapil Jetha; Suresh Kumar Verma; Pradeep Singh Rathore; Monika Choudhary

    2017-01-01

    ...,” in which the arterial changes are seen among patients with various syndromes or other disease processes- Down syndrome, sickle cell anaemia, neurofibromatosis type-1, congenital heart disease...

  6. Lipooligosaccharide locus classes and putative virulence genes among chicken and human Campylobacter jejuni isolates.

    Science.gov (United States)

    Ellström, Patrik; Hansson, Ingrid; Nilsson, Anna; Rautelin, Hilpi; Olsson Engvall, Eva

    2016-11-21

    Campylobacter cause morbidity and considerable economic loss due to hospitalization and post infectious sequelae such as reactive arthritis, Guillain Barré- and Miller Fischer syndromes. Such sequelae have been linked to C. jejuni harboring sialic acid structures in their lipooligosaccharide (LOS) layer of the cell wall. Poultry is an important source of human Campylobacter infections but little is known about the prevalence of sialylated C. jejuni isolates and the extent of transmission of such isolates to humans. Genotypes of C. jejuni isolates from enteritis patients were compared with those of broiler chicken with pulsed-field gel electrophoresis (PFGE), to study the patterns of LOS biosynthesis genes and other virulence associated genes and to what extent these occur among Campylobacter genotypes found both in humans and chickens. Chicken and human isolates generally had similar distributions of the putative virulence genes and LOS locus classes studied. However, there were significant differences regarding LOS locus class of PFGE types that were overlapping between chicken and human isolates and those that were distinct to each source. The study highlights the prevalence of virulence associated genes among Campylobacter isolates from humans and chickens and suggests possible patterns of transmission between the two species.

  7. Molecular analysis of the glucocerebrosidase gene locus

    Energy Technology Data Exchange (ETDEWEB)

    Winfield, S.L.; Martin, B.M.; Fandino, A. [Clinical Neuroscience Branch, Bethesda, MD (United States)] [and others

    1994-09-01

    Gaucher disease is due to a deficiency in the activity of the lysosomal enzyme glucocerebrosidase. Both the functional gene for this enzyme and a pseudogene are located in close proximity on chromosome 1q21. Analysis of the mutations present in patient samples has suggested interaction between the functional gene and the pseudogene in the origin of mutant genotypes. To investigate the involvement of regions flanking the functional gene and pseudogene in the origin of mutations found in Gaucher disease, a YAC clone containing DNA from this locus has been subcloned and characterized. The original YAC containing {approximately}360 kb was truncated with the use of fragmentation plasmids to about 85 kb. A lambda library derived from this YAC was screened to obtain clones containing glucocerebrosidase sequences. PCR amplification was used to identify subclones containing 5{prime}, central, or 3{prime} sequences of the functional gene or of the pseudogene. Clones spanning the entire distance from the last exon of the functional gene to intron 1 of the pseudogene, the 5{prime} end of the functional gene and 16 kb of 5{prime} flanking region and approximately 15 kb of 3{prime} flanking region of the pseudogene were sequenced. Sequence data from 48 kb of intergenic and flanking regions of the glucocerebrosidase gene and its pseudogene has been generated. A large number of Alu sequences and several simple repeats have been found. Two of these repeats exhibit fragment length polymorphism. There is almost 100% homology between the 3{prime} flanking regions of the functional gene and the pseudogene, extending to about 4 kb past the termination codons. A much lower degree of homology is observed in the 5{prime} flanking region. Patient samples are currently being screened for polymorphisms in these flanking regions.

  8. 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.

  9. [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.

  10. Psicologia e Arquitetura: em busca do locus interdisciplinar Psychology and Architecture: looking for the interdisciplinary locus

    Directory of Open Access Journals (Sweden)

    Gleice Azambuja Elali

    1997-12-01

    Full Text Available Partindo do reconhecimento da inevitável interdisciplinaridade no estudo da relação pessoa-ambiente, o artigo discute a Psicologia Ambiental enquanto locus privilegiado na interseção entre Psicologia e Arquitetura, com especial ênfase para a interrelação ambiente construído - comportamento humano. Definindo a escolha dos métodos de pesquisa como fator crucial a esta posição interdisciplinar, o texto aponta os principais métodos atualmente utilizados, facilidades de aplicação e vantagens/desvantagens dos mesmos, defendendo a propriedade do uso de multimétodos na realização de trabalhos na área.Acknowledging interdisciplinarity as an inevitable condition for the study of person-environment relationship, the article discusses Environmental Psychology as locus of intersection between Psychology and Architecture, converging upon the interrelationship human behavior - built environment. Considering that the choice of research methods is an essential element to such an approach, the text defines the main methods and techniques used in this area, their application and advantages/disadvantages, emphasizing a multi-method strategy.

  11. A locus for cerebral cavernous malformations maps to chromosome 7q in two families

    Energy Technology Data Exchange (ETDEWEB)

    Marchuk, D.A.; Gallione, C.J. [Duke Univ. Medical Center, Durham, NC (United States); Morrison, L.A.; Davis, L.E.; Clericuzio, C.L. [Univ. of New Mexico School of Medicine, Albuquerque, NM (United States)] [and others

    1995-07-20

    Cavernous malformations (angiomas) affecting the central nervous system and retina can be inherited in autosomal dominant pattern (OMIM 116860). These vascular lesions may remain clinically silent or lead to a number of neurological symptoms including seizure, intracranial hemorrhage, focal neurological deficit, and migraine. We have mapped a gene for this disorder in two families, one of Italian-American origin and one of Mexican-American origin, to markers on proximal 7q, with a combined maximum lod score of 3.92 ({theta} of zero) with marker D7S479. Haplotype analysis of these families places the locus between markers D7S502 proximally and D7S515 distally, an interval of approximately 41 cM. The location distinguishes this disorder from an autosomal dominant vascular malformation syndrome where lesions are primarily cutaneous and that maps to 9p21. 16 refs., 3 figs., 1 tab.

  12. Neurochemical and electrical modulation of the Locus coeruleus: contribution to CO2 drive to breathe

    Directory of Open Access Journals (Sweden)

    Debora eDe Carvalho

    2014-08-01

    Full Text Available The Locus coeruleus (LC is a dorsal pontine region, situated bilaterally on the floor of the fourth ventricle. It is considered to be the major source of noradrenergic innervation in the brain. These neurons are highly sensitive to CO2 / pH, and chemical lesions of LC neurons largely attenuate the hypercapnic ventilatory response in unanesthetized adult rats. Developmental dysfunctions in these neurons are linked to pathological conditions such as Rett and sudden infant death syndromes, which can impair the control of the cardio-respiratory system. LC is densely innervated by fibers that contain glutamate, serotonin and ATP, and these neurotransmitters strongly affect LC activity, including central chemoreflexes. Aside from neurochemical modulation, LC neurons are also strongly electrically coupled, specifically through gap junctions, which play a role in the CO2 ventilatory response. This article reviews the available data on the role of chemical and electrical neuromodulation of the LC in the control of ventilation.

  13. 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.

  14. The short-term effects of PMMA contact lens wear on keratometric behaviour: results for a single keratoconic cornea*

    Directory of Open Access Journals (Sweden)

    E. Chetty

    2010-12-01

    Full Text Available Keratometric behaviour is a multifaceted issue that many researchers have investigated for years. Many internal and external influences can have an effect on the cornea’s keratometric behaviour. This investigation forms a small part of a larger study that aims at determining the effects that rigid contact lenses might have on keratometric behaviour. This pilot study examined the keratometric behaviour of a single, mildly keratoconic cornea that was fitted with a polymethyl methacrylate (PMMA contact lens. Sixty successive auto-keratometric measurements were taken immediately before and immediately after three hours of contact lens wear. The data obtained was transformed to dioptric power matrices and were analysed using multivariate statistical methods. This study showed that, at least in one keratoconic cornea, there appeared to be a statistically significant change in corneal curvature under the influence of a PMMA contact lens. The contact lens had also appeared to decrease variation in corneal curvature. There was no control study done on this eye therefore the effects of diurnal variation, if any, could not be established. (S Afr Optom 2010 69(2 69-76

  15. 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.

  16. 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.

  17. Photography of shock waves during excimer laser ablation of the cornea. Effect of helium gas on propagation velocity.

    Science.gov (United States)

    Krueger, R R; Krasinski, J S; Radzewicz, C; Stonecipher, K G; Rowsey, J J

    1993-07-01

    Shadow photography of shock waves excited by means of a xenon chloride excimer laser was performed to determine the shock wave propagation velocity in air, nitrogen and helium. Energy densities between 500 and 2,000 mJ/cm2 were used to ablate a rotating rubber cylindrical target and porcine corneas. In ablating the rubber cylinder, a shock wave velocity of 3.3 km/s was generated in air and nitrogen at 40 ns; this decreased to 1.4 km/s at 320 ns. When helium was blown on the target, the velocity increased by a factor of approximately two, to 5.9 km/s at 40 ns and 2.7 km/s at 320 ns. We suggest that blowing helium on the surface of the cornea during excimer laser ablation may speed the dissipation of high-energy acoustic waves and gaseous particles, and thus reduce the exposure and transfer of heat energy to the surrounding tissue.

  18. Differentiating untreated and cross-linked porcine corneas of the same measured stiffness with optical coherence elastography

    Science.gov (United States)

    Li, Jiasong; Han, Zhaolong; Singh, Manmohan; Twa, Michael D.; Larin, Kirill V.

    2014-11-01

    Structurally degenerative diseases, such as keratoconus, can significantly alter the stiffness of the cornea, directly affecting the quality of vision. Ultraviolet-induced collagen cross-linking (CXL) effectively increases corneal stiffness and is applied clinically to treat keratoconus. However, measured corneal stiffness is also influenced by intraocular pressure (IOP). Therefore, experimentally measured changes in corneal stiffness may be attributable to the effects of CXL, changes in IOP, or both. We present a noninvasive measurement method using phase-stabilized swept-source optical coherence elastography to distinguish between CXL and IOP effects on measured corneal stiffness. This method compared the displacement amplitude attenuation of a focused air-pulse-induced elastic wave. The damping speed of the displacement amplitudes at each measurement position along the wave propagation were compared for different materials. This method was initially tested on gelatin and agar phantoms of the same stiffness for validation. Consequently, untreated and CXL-treated porcine corneas of the same measured stiffness, but at different IOPs, were also evaluated. The results suggest that this noninvasive method may have the potential to detect the early stages of ocular diseases such as keratoconus or may be applied during CLX procedures by factoring in the effects of IOP on the measured corneal stiffness.

  19. In vitro evaluation of the permeation enhancing effect of polycarbophil-cysteine conjugates on the cornea of rabbits.

    Science.gov (United States)

    Hornof, Margit D; Bernkop-Schnürch, Andreas

    2002-12-01

    It was the aim of this study to investigate the permeation enhancing effect of thiolated polycarbophil on the cornea of rabbits in vitro. The proposed reaction mechanism involves the opening of the tight junctions in the corneal epithelium. The modification of polycarbophil was achieved via covalent attachment of L-cysteine mediated by a carbodiimide. Transcorneal permeation studies were performed in Ussing-type diffusion chambers. As model compounds, sodium fluorescein, as a marker for paracellular transport, and dexamethasone phosphate were used. To evaluate potential corneal damage the corneal hydration level of each cornea was determined. Polycarbophil-cysteine was found to increase the permeation of sodium fluorescein 2.2-fold and that of dexamethasone phosphate 2.4-fold in comparison to the unmodified polymer. The concentration of dexamethasone in the acceptor medium was 1.5-fold increased. As evidenced by the corneal hydration level, polycarbophil-cysteine did not damage the corneal tissues. Therefore, polycarbophil-cysteine conjugates seem to be promising excipients for ocular drug delivery systems where they might be used as safe permeation enhancers.

  20. Toxic endothelial cell destruction of the cornea after routine extracapsular cataract surgery.

    Science.gov (United States)

    Breebaart, A C; Nuyts, R M; Pels, E; Edelhauser, H F; Verbraak, F D

    1990-08-01

    Eighteen patients developed an acute corneal decompensation following normal intraocular surgery (cataract extraction in 17 patients), characterized by star-shaped endothelial folds, a twofold increase in corneal thickness, and a visual acuity of counting fingers during several postoperative days. In some cases, there was an additional iritis and transient hypotony. There was no effect of topical and/or subconjunctival corticosteroids on the course of the decompensation. Endothelial morphometric analysis showed a mean endothelial cell loss of 72%. Endothelial wound healing, as determined by coefficient of variation and percentage hexagonals, stabilized 6 months postoperatively. We coined the term toxic endothelial cell destruction for this syndrome. Epidemiological evaluation revealed the toxic endothelial cell destruction syndrome to be linked with the 10-fold increase of a detergent solution in the ultrasonic bath for cleaning the surgical instruments.

  1. Differential Effects of Dexamethasone and Doxycycline on Inflammation and MMP Production in Murine Alkali-Burned Corneas Associated with Dry Eye.

    Science.gov (United States)

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

    2016-04-01

    Alkali burns to the cornea are among the most devastating injuries to the eye. The purpose of this study was to evaluate the effects of dexamethasone (Dex) or doxycycline (Doxy) on protease activity and corneal complications in a combined model (CM) of alkali burn and dry eye. C57BL/6 mice were subjected to the CM for 2 or 5 days (D). Mice were topically treated either with Dex (0.1%), Dox (0.025%) or vehicle QID and observed daily for appearance of corneal perforation. Quantitative real time PCR was performed to measure expression of inflammation cytokines and matrix metalloproteinases (MMPs) in whole cornea lysates. No perforations were observed in the Dex-treated corneas. All wounds in Doxy-treated corneas were closed 2D post-injury, and they had significantly lower corneal opacity scores at days 4 and 5 post-injury compared to BSS treatment. Dex-treated corneas had the lowest corneal opacity scores. Dex treatment significantly decreased expression of IL-1β, IL-6, MMPs -1, -9, -13, and TIMP-1 after 2 days but increased levels of MMP-8, while Doxy treatment significantly decreased IL-1β, IL-6, MMP-8, and -9, compared to vehicle. Decreased MMP-1, -9 and -13 immunoreactivity and gelatinolytic activity were seen in corneas treated with Doxy and Dex compared to vehicle. Increased neutrophil infiltration and myeloperoxidase activity was noted in the vehicle group compared to Dex 2 days post-injury. These findings demonstrate that early initiation of anti-inflammatory therapy is very efficacious in preserving corneal clarity and facilitating wound healing, while modulating MMP production and suppressing neutrophil infiltration. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Pyogenic arthritis, pyoderma gangrenosum, and acne syndrome maps to chromosome 15q.

    Science.gov (United States)

    Yeon, H B; Lindor, N M; Seidman, J G; Seidman, C E

    2000-04-01

    Pyoderma gangrenosum, cystic acne, and aseptic arthritis are clinically distinct disorders within the broad class of inflammatory diseases. Although this triad of symptoms is rarely observed in a single patient, a three-generation kindred with autosomal-dominant transmission of these three disorders has been reported as "PAPA syndrome" (MIM 604416). We report mapping of a disease locus for familial pyoderma gangrenosum-acne-arthritis to the long arm of chromosome 15 (maximum two-point LOD score, 5.83; recombination fraction [straight theta] 0 at locus D15S206). Under the assumption of complete penetrance, haplotype analysis of recombination events defined a disease interval of 10 cM, between D15S1023 and D15S979. Successful identification of a single disease locus for this syndrome suggests that these clinically distinct disorders may share a genetic etiology. These data further indicate the role of genes outside the major histocompatibility locus in inflammatory disease.

  3. Kindler syndrome

    Directory of Open Access Journals (Sweden)

    Kaviarasan P

    2005-01-01

    Full Text Available Kindler syndrome is a rare autosomal recessive disorder associated with skin fragility. It is characterized by blistering in infancy, photosensitivity and progressive poikiloderma. The syndrome involves the skin and mucous membrane with radiological changes. The genetic defect has been identified on the short arm of chromosome 20. This report describes an 18-year-old patient with classical features like blistering and photosensitivity in childhood and the subsequent development of poikiloderma. The differential diagnosis of Kindler syndrome includes diseases like Bloom syndrome, Cockayne syndrome, dyskeratosis congenita, epidermolysis bullosa, Rothmund-Thomson syndrome and xeroderma pigmentosum. Our patient had classical cutaneous features of Kindler syndrome with phimosis as a complication.

  4. Research progress in scaffolds of tissue engineered cornea%组织工程化角膜支架的研究进展

    Institute of Scientific and Technical Information of China (English)

    张凯

    2012-01-01

    近20年来,应用组织工程技术构建角膜组织——组织工程化角膜的构建取得了较大的进展.然而,能够广泛应用于临床的组织工程化角膜的构建仍不够完善.组织工程化角膜支架是构建组织工程化角膜的重要组成部分之一.探寻生物相容性好、可降解并具有足够生物力学强度的支架材料是组织工程化角膜研究领域亟待解决的课题.就组织工程化角膜支架的发展历程进行概括总结,评价不同支架材料的优缺点,拓展理想支架材料的研发视野,为可广泛用于临床的组织工程化角膜的研制提供信息.%Great progress has been made in tissue engineering cornea construction (i.c.constructing human corneal equivalence by using tissue engineering technique) during the past 20 years.However,a kind of tissue engineering cornea which can be applied to corneal transplantation as human cornea equivalent is yet to be availablc.Scaffold is an indispensable part of tissue engineering cornea.Searching for some kinds of scaffolds with good biocompability,some extent of biodegradation and euough biomechanics property are the issue needing to be resolved immediately in the tissue engineering cornea filed.This article reviewed the development of tissue engineering cornea scaffolds,represented the merits and defects of different scaffolds in order to optimize the project of choosing scaffolds and furthermore lay the foundation for constructing a kind of tissue engineering cornea which may be applied to corneal transplantation as human cornea equivalent in the future.

  5. Two-photon spectral fluorescence lifetime and second-harmonic generation imaging of the porcine cornea with a 12-femtosecond laser microscope

    Science.gov (United States)

    Batista, Ana; Breunig, Hans Georg; Uchugonova, Aisada; Morgado, António Miguel; König, Karsten

    2016-03-01

    Five dimensional microscopy with a 12-fs laser scanning microscope based on spectrally resolved two-photon autofluorescence lifetime and second-harmonic generation (SHG) imaging was used to characterize all layers of the porcine cornea. This setup allowed the simultaneous excitation of both metabolic cofactors, NAD(P)H and flavins, and their discrimination based on their spectral emission properties and fluorescence decay characteristics. Furthermore, the architecture of the stromal collagen fibrils was assessed by SHG imaging in both forward and backward directions. Information on the metabolic state and the tissue architecture of the porcine cornea were obtained with subcellular resolution, and high temporal and spectral resolutions.

  6. Microbiological profile of donor corneas stored for tectonic transplantation purposes in rabbits Microbiologia de amostras de bancos de córneas destinadas a transplantes, em coelhos

    Directory of Open Access Journals (Sweden)

    K.K. Kobashigawa

    2013-02-01

    Full Text Available This study aimed to evaluate the microbiota of donor rabbit corneas stored for tectonic transplantation purposes. Swabs from both corneas of 20 rabbits were carefully collected and submitted to microorganism isolation and identification. After this first swab collection, rabbits were euthanized for reasons other than this project and the eyes were enucleated. The corneas were collected and stored to compose the cornea tissue bank. Corneas were stored in a 0.3% tobramycin solution at -20ºC. After 30 days, the corneas were thawed at room temperature and removed from the antibiotic. New swabs were obtained from the corneas and submitted to microorganism isolation and identification. Gram positive organisms were predominant in the rabbit corneal flora before storage and the Staphylococcus sp. was the most common microorganism isolated from those samples. No growth was observed on the samples collected after storage. The methods used for collection and storage of the corneas were efficient to constitute a sterile donor corneal tissue bank.Analisaram-se córneas armazenadas para transplantes tectônicos usando-se suabes coletados de 20 coelhos, visando ao isolamento e à identificação de microrganismos. Após a coleta das amostras, os coelhos foram submetidos à eutanásia, por razões alheias ao estudo, e enucleados. As córneas foram coletadas e armazenadas a fim de se constituir o banco de córneas. O armazenamento deu-se em solução de tobramicina 0,3% a -20ºC, por 30 dias. Após esse período, as córneas foram descongeladas à temperatura ambiente e removidas da solução de antibiótico. Novos suabes foram coletados e submetidos ao isolamento e à identificação dos microrganismos. A flora corneal mostrou-se predominantemente composta por bactérias Gram positivas, sendo o Staphylococcus sp. o mais identificado. Não se verificou crescimento de colônias bacterianas ou fúngicas nas amostras após o armazenamento. Considerando-se a

  7. Genetic mapping of the hereditary mixed polyposis syndrome to chromosome 6q

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, H.J.W.; Whitelaw, S.C.; Hodgson, S.V.; Northover, J.M.A.; Talbot, I.C. [and others

    1996-04-01

    Hereditary mixed polyposis syndrome (HMPS) is characterized by atypical juvenile polyps, colonic adenomas, and colorectal carcinomas. HMPS appears to be inherited in an autosomal dominant manner. Genetic linkage analysis has been performed on a large family with HMPS. Data did not support linkage to the APC locus or to any of the loci for hereditary nonpolyposis colorectal cancer. Evidence that the HMPS locus lies on chromosome 6q was, however, provided by significant two-point LOD scores for linkage between HMPS and the D6S283 locus. Analysis of recombinants and multipoint linkage analysis suggested that the HMPS locus lies in a 4-cM interval containing the D6S283 locus and flanked by markers D6S468 and D6S301. 10 refs., 4 figs., 1 tab.

  8. Replication of an Association Between the Lymphoid Tyrosine Phosphatase Locus (LYP/PTPN22) With Type 1 Diabetes, and Evidence for Its Role as a General Autoimmunity Locus

    National Research Council Canada - National Science Library

    Deborah Smyth; Jason D. Cooper; Joanne E. Collins; Joanne M. Heward; Jayne A. Franklyn; Joanna M.M. Howson; Adrian Vella; Sarah Nutland; Helen E. Rance; Lisa Maier; Bryan J. Barratt; Cristian Guja; Constantin Ionescu-Tı̂rgovişte; David A. Savage; David B. Dunger; Barry Widmer; David P. Strachan; Susan M. Ring; Neil Walker; David G. Clayton; Rebecca C.J. Twells; Stephen C.L. Gough; John A. Todd

    2004-01-01

    Replication of an Association Between the Lymphoid Tyrosine Phosphatase Locus ( LYP/PTPN22 ) With Type 1 Diabetes, and Evidence for Its Role as a General Autoimmunity Locus Deborah Smyth 1 , Jason D...

  9. 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

  10. 人工角膜及其相关材料%Artificial cornea and related materials

    Institute of Scientific and Technical Information of China (English)

    严拓; 敖宁建; 覃百花; 邓华

    2008-01-01

    学术背景:对于同种异体角膜移植失败的患者,人工角膜移植便成了复明的惟一希望.人工角膜的研究虽然已经跨越2个世纪,但由于各种因素限制,角膜植入术仍然只能在少数中心开展.近年来,由于相关学科的飞速发展,人工角膜也进入了快速发展时期.目的:从材料选择、片型设计、材料改性以及临床试验等角度进行叙述,比较不同结构人工角膜各自特点,并指出目前人工角膜所存在的主要问题,对理想的人工角膜提出了新的见解.检索策略:作者应用计算机检索中国全文期刊数据库(CNKI),Springer,EI,Blackwell数据库1993-01/2007-12与人工角膜相关文献.所用中文检索词有"人工角膜、角膜穿透术";英文榆索词包括"artificial cornea,penetrating keratoplasty".纳入标准:文章内容与人工角膜材料、片型设计、临床研究有关.排除标准:较为陈旧,重复性研究.文献评价:共检索到86篇相关文献,68篇文献符合上述要求,其中12篇为综述性文献,37篇为基础性研究文献,19篇为临床研究文献,从中选择30篇进行综述.资料综合:人工角膜材料包括光学镜柱材料(水凝胶、聚甲基丙烯酸甲酯、硅凝胶、玻璃)和支架材料(氟碳聚合物、羟基磷灰石、生物材料).材料改性包括材料化学改性、材料表面处理、材料表面修饰、材料表面等离子处理.不同的角膜片型设计中,较为成功的是AlphaCor和Osteo-Odonto,并获得了美国食品药品管理局批准,进入临床阶段.结论:提高人工角膜与组织黏附度,减少并发症是长期研究的重点领域,而材料选择、材料改性、片型设计等是解决的关键.

  11. Acro-Dermato-Ungual-Lacrimal-Tooth Syndrome: An Uncommon Member of the Ectodermal Dysplasias.

    Science.gov (United States)

    Whittington, Adam; Stein, Sarah; Kenner-Bell, Brandi

    2016-09-01

    Acro-dermato-ungual-lacrimal-tooth (ADULT) syndrome is a rare form of autosomal dominant ectodermal dysplasia due to mutations in the TP63 gene, a locus that has also been implicated in other syndromic forms of ectodermal dysplasia. It shares many phenotypic characteristics with other TP63 gene mutation syndromes, often making an accurate diagnosis difficult. Long-term management and follow-up of the various sequelae of ectodermal dysplasia require an accurate diagnosis. We report a familial case of ADULT syndrome in a daughter, mother, and son and provide a brief review of the clinical characteristics of this syndrome.

  12. 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.

  13. Germline mutations in DIS3L2 cause the Perlman syndrome of overgrowth and Wilms tumor susceptibility

    NARCIS (Netherlands)

    Astuti, Dewi; Morris, Mark R.; Cooper, Wendy N.; Staals, Raymond H. J.; Wake, Naomi C.; Fews, Graham A.; Gill, Harmeet; Gentle, Dean; Shuib, Salwati; Ricketts, Christopher J.; Cole, Trevor; van Essen, Anthonie J.; van Lingen, Richard A.; Neri, Giovanni; Opitz, John M.; Rump, Patrick; Stolte-Dijkstra, Irene; Mueller, Ferenc; Pruijn, Ger J. M.; Latif, Farida; Maher, Eamonn R.

    2012-01-01

    Perlman syndrome is a congenital overgrowth syndrome inherited in an autosomal recessive manner that is associated with Wilms tumor susceptibility. We mapped a previously unknown susceptibility locus to 2q37.1 and identified germline mutations in DIS3L2, a homolog of the Schizosaccharomyces pombe di

  14. Loss of the BMP Antagonist, SMOC-1, Causes Ophthalmo-Acromelic (Waardenburg Anophthalmia) Syndrome in Humans and Mice

    NARCIS (Netherlands)

    J. Rainger; E. van Beusekom; J.K. Ramsay; L. McKie; L. Al-Gazali; R. Pallotta; A. Saponari; P. Branney; M. Fisher; H. Morrison; L. Bicknell; P. Gautier; P. Perry; K. Sokhi; D. Sexton; T.M. Bardakjian; A.S. Schneider; N. Elcioglu; F. Ozkinay; R. Koenig; A. Megarbane; C.N. Semerci; A. Khan; S. Zafar; R. Hennekam; S.B. Sousa; L. Ramos; L. Garavelli; A.S. Furga; A. Wischmeijer; I.J. Jackson; G. Gillessen-Kaesbach; H.G. Brunner; D Wieczorek; H. van Bokhoven; D.R. Fitzpatrick

    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 identif

  15. 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 identif

  16. 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.

  17. 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.

  18. 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.

  19. Adenoviral Gene Therapy for Diabetic Keratopathy: Effects on Wound Healing and Stem Cell Marker Expression in Human Organ-cultured Corneas and Limbal Epithelial Cells.

    Science.gov (United States)

    Kramerov, Andrei A; Saghizadeh, Mehrnoosh; Ljubimov, Alexander V

    2016-04-07

    The goal of this protocol is to describe molecular alterations in human diabetic corneas and demonstrate how they can be alleviated by adenoviral gene therapy in organ-cultured corneas. The diabetic corneal disease is a complication of diabetes with frequent abnormalities of corneal nerves and epithelial wound healing. We have also documented significantly altered expression of several putative epithelial stem cell markers in human diabetic corneas. To alleviate these changes, adenoviral gene therapy was successfully implemented using the upregulation of c-met proto-oncogene expression and/or the downregulation of proteinases matrix metalloproteinase-10 (MMP-10) and cathepsin F. This therapy accelerated wound healing in diabetic corneas even when only the limbal stem cell compartment was transduced. The best results were obtained with combined treatment. For possible patient transplantation of normalized stem cells, an example is also presented of the optimization of gene transduction in stem cell-enriched cultures using polycationic enhancers. This approach may be useful not only for the selected genes but also for the other mediators of corneal epithelial wound healing and stem cell function.

  20. Herpes simplex virus-specific T cells infiltrate the cornea of patients with herpetic stromal keratitis: no evidence for autoreactive T cells

    NARCIS (Netherlands)

    L. Remeijer (Lies); C.M. Mooy (Cornelia); A.D.M.E. Osterhaus (Albert); G.M.G.M. Verjans (George)

    2000-01-01

    textabstractPURPOSE: Herpetic stromal keratitis (HSK) is a T-cell-mediated inflammatory disease initiated by a herpes simplex virus (HSV) infection of the cornea. Recently, studies in the HSK mouse model have shown that the immunopathogenic T cells are directed against the HSV prot

  1. 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.

  2. Central corneal thickness measurement using ultrasonic pachymetry, rotating scheimpflug camera, and scanning-slit topography exclusively in thin non-keratoconic corneas

    Directory of Open Access Journals (Sweden)

    Mehrdad Mohammadpour

    2016-01-01

    Conclusion: In normal thin corneas, Pentacam demonstrated better agreement with US pachymetry as compared to corrected Orbscan readings. Results achieved by Orbscan were better consistent with US pachymetry using an AF of 0.94. We speculate that a dynamically graded AF in reverse proportion to CCT constitutes a better approach for correcting Orbscan measurements.

  3. Amniotic membrane immobilized poly(vinyl alcohol) hybrid polymer as an artificial cornea scaffold that supports a stratified and differentiated corneal epithelium.

    Science.gov (United States)

    Uchino, Yuichi; Shimmura, Shigeto; Miyashita, Hideyuki; Taguchi, Tetsushi; Kobayashi, Hisatoshi; Shimazaki, Jun; Tanaka, Junzo; Tsubota, Kazuo

    2007-04-01

    Poly(vinyl alcohol) (PVA) is a biocompatible, transparent hydrogel with physical strength that makes it promising as a material for an artificial cornea. In our previous study, type I collagen was immobilized onto PVA (PVA-COL) as a possible artificial cornea scaffold that can sustain a functional corneal epithelium. The cellular adhesiveness of PVA in vitro was improved by collagen immobilization; however, stable epithelialization was not achieved in vivo. To improve epithelialization in vivo, we created an amniotic membrane (AM)-immobilized polyvinyl alcohol hydrogel (PVA-AM) for use as an artificial cornea material. AM was attached to PVA-COL using a tissue adhesive consisting of collagen and citric acid derivative (CAD) as a crosslinker. Rabbit corneal epithelial cells were air-lift cultured with 3T3 feeder fibroblasts to form a stratified epithelial layer on PVA-AM. The rabbit corneal epithelial cells formed 3-5 layers of keratin-3-positive epithelium on PVA-AM. Occludin-positive cells were observed lining the superficial epithelium, the gap-junctional protein connexin43-positive cells was localized to the cell membrane of the basal epithelium, while both collagen IV were observed in the basement membrane. Epithelialization over implanted PVA-AM was complete within 2 weeks, with little inflammation or opacification of the hydrogel. Corneal epithelialization on PVA-AM in rabbit corneas improved over PVA-COL, suggesting the possibility of using PVA-AM as a biocompatible hybrid material for keratoprosthesis. (c) 2006 Wiley Periodicals, Inc.

  4. Development of a serum-free human cornea construct for in vitro drug absorption studies: the influence of varying cultivation parameters on barrier characteristics.

    Science.gov (United States)

    Hahne, Matthias; Reichl, Stephan

    2011-09-15

    The increased use of ophthalmic products in recent years has led to an increased demand for in vitro and in vivo transcorneal drug absorption studies. Cell-culture models of the human cornea can avoid several of the disadvantages of widely used animal experimental models, including ethical concerns and poor standardisation. This study describes the development of a serum-free cultivated, three-dimensional human cornea model (Hemicornea, HC) for drug absorption experiments. The impact of varying cultivation conditions on the corneal barrier function was analysed and compared with excised rabbit and porcine corneas. The HC was cultivated on permeable polycarbonate filters using immortalised human keratocytes and a corneal epithelial cell line. The equivalence to native tissue was investigated through absorption studies using model substances with a wide range of molecular characteristics, including hydrophilic sodium fluorescein, lipophilic rhodamine B and fluorescein isothiocyanate (FITC)-labelled macromolecule dextran. To study the intra-laboratory repeatability and construct cultivation, the permeation studies were performed independently by different researchers. The HC exhibited a permeation barrier in the same range as excised animal corneas, high reproducibility and a lower standard deviation. Therefore, the HC could be a promising in vitro alternative to ex vivo corneal tissues in preclinical permeation studies.

  5. Parenting style, locus of control, and oral hygiene in adolescents.

    Science.gov (United States)

    Aleksejūnienė, Jolanta; Brukienė, Vilma

    2012-01-01

    The aim of the study was to test if variations in oral hygiene levels in adolescents were associated with locus of control and parenting styles after controlling for demographic factors. The study sample comprised 237 adolescents aged 12-13 years. The structured questionnaire included demographic characteristics and items about parenting style and locus of control. The Individual Quantitative Plaque % Index (IQPI) and toothbrushing frequency were used as clinical outcome measures. In the bivariate analyses, socioeconomic status (P=0.012), number of children in the family (P=0.003), and frequency of toothbrushing (P=0.001) were related to dental plaque levels. Gender (Pparenting styles, locus of control, and oral hygiene levels was not confirmed.

  6. Lupus vulgaris occurring in a locus minoris resistentiae.

    Science.gov (United States)

    Long, Richard; Beatch, Anita; Lee, Mao-Cheng; Cheung-Lee, Melody; Wasel, Norman

    2009-01-01

    The pathogenesis of lupus vulgaris, a form of cutaneous tuberculosis, is not always clear, especially in patients who do not have coexistent extracutaneous tuberculosis and in patients with single lesions. To report a case of lupus vulgaris in a locus minoris resistentiae (a site of reduced resistance) and to use a unique set of clinical circumstances and laboratory tests to reconstruct the pathogenesis of the lesion and the response to treatment. Lupus vulgaris can occur in a locus minoris resistentiae; local trauma and possibly other factors, such as increased temperature, topical corticosteroids, and the virulence of the infecting strain, may facilitate the growth of Mycobacterium tuberculosis present at a locus minoris resistentiae as a result of a silent bacillemia.

  7. Desire for control, locus of control, and proneness to depression.

    Science.gov (United States)

    Burger, J M

    1984-03-01

    Two personality constructs, desire for control and locus of control, were related to depression among college students. Measures of levels of depression, desire for control, and locus of control were taken from subjects. Approximately six months later 71% of these subjects returned a questionnaire concerning their experiences with depression during that six-month period. It was found that locus of control scores, particularly the extent to which subjects perceived that their lives were controlled by chance, were significantly related to the depression levels. It was also found that high desire for control subjects who held external perceptions of control were most likely to seek nonprofessional help for depression. In addition, high desire for control subjects who perceived their lives as generally controlled by chance were most likely to have suicidal thoughts. The results are interpreted in terms of a general style that may promote a proneness to depression for certain individuals.

  8. 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

  9. 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.

  10. 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

  11. LL-37 via EGFR transactivation to promote high glucose-attenuated epithelial wound healing in organ-cultured corneas.

    Science.gov (United States)

    Yin, Jia; Yu, Fu-Shin X

    2010-04-01

    Purpose. Patients with diabetes are at higher risk for delayed corneal reepithelialization and infection. Previous studies indicated that high glucose (HG) impairs epidermal growth factor receptor (EGFR) signaling and attenuates ex vivo corneal epithelial wound healing. The authors investigated the effects of antimicrobial peptide LL-37 on HG-attenuated corneal epithelial EGFR signaling and wound closure. Methods. Human corneal epithelial cells (HCECs) were stimulated with LL-37. Heparin-binding EGF-like growth factor (HB-EGF) shedding was assessed by measuring the release of alkaline phosphatase (AP) in a stable HCEC line expressing HB-EGF-AP. Activation of EGFR, phosphoinositide 3-kinase (PI3K), and extracellular signal-regulated kinases 1/2 (ERK1/2) was determined by Western blot analysis. Corneal epithelial wound closure was assessed in cultured HCECs and porcine corneas. LL-37 expression was determined by immune dot blot. Results. LL-37 induced HB-EGF-AP release and EGFR activation in a dose-dependent manner. LL-37 prolonged EGFR signaling in response to wounding. LL-37 enhanced the closure of a scratch wound in cultured HCECs and partially rescued HG-attenuated wound healing in an EGFR- and a PI3K-dependent manner and restored HG-impaired EGFR signaling in cultured porcine corneas. HG attenuated wounding-induced LL-37 expression in cultured HCECs. Conclusions. LL-37 is a tonic factor promoting EGFR signaling and enhancing epithelial wound healing in normal and high glucose conditions. With both antimicrobial and regenerative capabilities, LL-37 may be a potential therapeutic for diabetic keratopathy.

  12. Three dimensional visualization and fractal analysis of mosaic patches in rat chimeras: cell assortment in liver, adrenal cortex and cornea.

    Science.gov (United States)

    Iannaccone, Stephen; Zhou, Yue; Walterhouse, David; Taborn, Greg; Landini, Gabriel; Iannaccone, Philip

    2012-01-01

    The production of organ parenchyma in a rapid and reproducible manner is critical to normal development. In chimeras produced by the combination of genetically distinguishable tissues, mosaic patterns of cells derived from the combined genotypes can be visualized. These patterns comprise patches of contiguously similar genotypes and are different in different organs but similar in a given organ from individual to individual. Thus, the processes that produce the patterns are regulated and conserved. We have previously established that mosaic patches in multiple tissues are fractal, consistent with an iterative, recursive growth model with simple stereotypical division rules. Fractal dimensions of various tissues are consistent with algorithmic models in which changing a single variable (e.g. daughter cell placement after division) switches the mosaic pattern from islands to stripes of cells. Here we show that the spiral pattern previously observed in mouse cornea can also be visualized in rat chimeras. While it is generally held that the pattern is induced by stem cell division dynamics, there is an unexplained discrepancy in the speed of cellular migration and the emergence of the pattern. We demonstrate in chimeric rat corneas both island and striped patterns exist depending on the age of the animal. The patches that comprise the pattern are fractal, and the fractal dimension changes with the age of the animal and indicates the constraint in patch complexity as the spiral pattern emerges. The spiral patterns are consistent with a loxodrome. Such data are likely to be relevant to growth and cell division in organ systems and will help in understanding how organ parenchyma are generated and maintained from multipotent stem cell populations located in specific topographical locations within the organ. Ultimately, understanding algorithmic growth is likely to be essential in achieving organ regeneration in vivo or in vitro from stem cell populations.

  13. Evaluation of Intrastromal Riboflavin Concentration in Human Corneas after Three Corneal Cross-Linking Imbibition Procedures: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Antonella Franch

    2015-01-01

    Full Text Available Purpose. To compare stromal riboflavin concentration after three corneal cross-linking (CXL imbibition procedures: standard (EpiOff, transepithelial corneal (EpiOn, and iontophoresis-assisted technique (Ionto using 0.1% hypotonic riboflavin phosphate. Methods. Randomized open-label pilot clinical study. Twelve corneas/12 patients with advanced keratoconus were randomly divided into 4 groups for CXL (n=3. The corneas underwent imbibition with standard riboflavin EpiOff and with enhanced riboflavin solution (RICROLIN+ EpiOff, EpiOn, and iontophoresis techniques. Thereafter, deep anterior lamellar keratectomy procedure was performed and the obtained debrided corneal tissues were frozen. The maximal intrastromal riboflavin concentration was measured by high-performance liquid chromatography/mass spectrometry (mcg/dg. Results. The mean stromal concentration of riboflavin was 2.02±0.72 mcg/dg in EpiOff group, 4.33±0.12 mcg/g in EpiOff-RICROLIN+ group, 0.63±0.21 mcg/dg in EpiOn-RICROLIN+ group, and 1.15±0.27 mcg/dg in iontophoresis RICROLIN+ group. A 7-fold decrease in intrastromal riboflavin concentration was observed comparing EpiOn-RICROLIN+ and EpiOff-RICROLIN+ groups. Conclusion. The present pilot study indicates that both transepithelial CXL techniques in combination with hypotonic enhanced riboflavin formulation (RICROLIN+ were still inferior to the standard CXL technique; however, larger clinical studies to further validate the results are needed and in progress.

  14. Three dimensional visualization and fractal analysis of mosaic patches in rat chimeras: cell assortment in liver, adrenal cortex and cornea.

    Directory of Open Access Journals (Sweden)

    Stephen Iannaccone

    Full Text Available The production of organ parenchyma in a rapid and reproducible manner is critical to normal development. In chimeras produced by the combination of genetically distinguishable tissues, mosaic patterns of cells derived from the combined genotypes can be visualized. These patterns comprise patches of contiguously similar genotypes and are different in different organs but similar in a given organ from individual to individual. Thus, the processes that produce the patterns are regulated and conserved. We have previously established that mosaic patches in multiple tissues are fractal, consistent with an iterative, recursive growth model with simple stereotypical division rules. Fractal dimensions of various tissues are consistent with algorithmic models in which changing a single variable (e.g. daughter cell placement after division switches the mosaic pattern from islands to stripes of cells. Here we show that the spiral pattern previously observed in mouse cornea can also be visualized in rat chimeras. While it is generally held that the pattern is induced by stem cell division dynamics, there is an unexplained discrepancy in the speed of cellular migration and the emergence of the pattern. We demonstrate in chimeric rat corneas both island and striped patterns exist depending on the age of the animal. The patches that comprise the pattern are fractal, and the fractal dimension changes with the age of the animal and indicates the constraint in patch complexity as the spiral pattern emerges. The spiral patterns are consistent with a loxodrome. Such data are likely to be relevant to growth and cell division in organ systems and will help in understanding how organ parenchyma are generated and maintained from multipotent stem cell populations located in specific topographical locations within the organ. Ultimately, understanding algorithmic growth is likely to be essential in achieving organ regeneration in vivo or in vitro from stem cell populations.

  15. Confocal microscopy of epithelial and langerhans cells of the cornea in patients using travoprost drops containing two different preservatives.

    Science.gov (United States)

    Marsovszky, László; Resch, Miklós D; Visontai, Zsuzsanna; Németh, János

    2014-07-01

    The recently developed confocal cornea microscopy offers the opportunity to examine pathologies of the cornea and to gain insight into the activity of innate immunity. We aimed to investigate the corneal epithelial and Langerhans cell (LC) densities along with dry eye parameters in primary open-angle glaucoma (POAG) subjects, treated with either of two commercially available travoprost 0.004 % topical medications containing different preservatives. (1: benzalkonium chloride 0.015 % (TravBAK) and 2: polyquaternium-1 (PQ) 0.001 % (TravPQ). Consecutive case series of nineteen POAG patients on TravBAK (mean age: 64.8 ± 13.6 years), nineteen POAG patients on TravPQ (mean age: 66.8 ± 11.3 years) and nineteen age-matched healthy control subjects (63.8 ± 8.2 years). Ocular surface disease index (OSDI), lid parallel conjunctival folds (LIPCOF), Schirmer test (ST) and tear break up time (TBUT) were assessed, and then corneal epithelial and LC densities were investigated with confocal microscopy. Tear production was significantly reduced in both glaucoma patient groups compared to healthy individuals (p < 0.05). TBUT was significantly reduced and epithelial cell densities were significantly greater in patients treated with TravBAK compared to healthy individuals (p < 0.05 for all). LC densities were greater in both glaucoma groups compared to control subjects (p < 0.05 for all). Travoprost therapy may compromise ocular surface. The limited alertness of the corneal immune system found in patients with TravPQ can be considered as indicators of a less disturbed ocular surface and better controlled corneal homeostasis.

  16. Fragile X Syndrome

    Directory of Open Access Journals (Sweden)

    Wilmar Saldarriaga

    2015-01-01

    Full Text Available Fragile X Syndrome (FXS is a genetic disease due to a CGG trinucleotide expansion, named full mutation (greater than 200 CGG repeats, in the fragile X mental retardation 1 gene locus Xq27.3; which leads to an hypermethylated region in the gene promoter therefore silencing it and lowering the expression levels of the fragile X mental retardation 1, a protein involved in synaptic plasticity and maturation.  Individuals with FXS present with intellectual disability, autism, hyperactivity, long face, large or prominent ears and macroorchidism at puberty and thereafter. Most of the young children with FXS will present with language delay, sensory hyper arousal and anxiety. Girls are less affected than boys, only 25% have intellectual disability. Given the genomic features of the syndrome, there are patients with a number of triplet repeats between 55 and 200, known as premutation carriers. Most carriers have a normal IQ but some have developmental problems. The diagnosis of FXS has evolved from karyotype with special culture medium, to molecular techniques that are more sensitive and specific including PCR and Southern Blot. During the last decade, the advances in the knowledge of FXS, has led to the development of investigations on pharmaceutical management or targeted treatments for FXS. Minocycline and sertraline have shown efficacy in children.

  17. Rett Syndrome -- an update.

    Science.gov (United States)

    Jellinger, K A

    2003-06-01

    Rett syndrome is a progressive, usually sporadic and rarely familial, disabling neurodevelopmental disorder with onset in early childhood presenting clinically with mental retardation, behavioral changes, late movement disturbances, loss of speech and hand skills, ataxia, apraxia, irregular breathing with hyperventilation while awake, and frequent seizures. It occurs almost exclusively in females with an estimated prevalence of 1 in 10-22000 births and is considered a manifestation of defective brain maturation caused by dominant mutation of the MeCP2 gene encoding the transcriptional repressor methyl-CpG-binding protein 2 related to the Xq28 locus. Although many different mutations of this protein are being studied in humans and in mice, the molecular pathogenesis of this disorder remains unclear. Electroencephalography is abnormal in the final stages of the syndrome. Neuroimaging showing brain atrophy may be required for differential diagnosis that includes neurodegenerative and metabolic disorders. Neuropathology shows decreased brain growth and reduced size of individual neurons, with thinned dendrites in some cortical layers and abnormalities in substantia nigra (decreased neuromelanin content), suggestive of deficient synaptogenic development, probably starting before birth. Neurometabolic changes include reduced levels of dopamine, serotonin, noradrenalin, choline acetyltransferase (ChAT), nerve growth factors, endorphines, glutamate, and other amino acids and their receptor levels in brain. Current treatment includes symptomatic, anticonvulsive and physiotherapy.

  18. Syndromic autism: II. Genetic syndromes associated with autism

    National Research Council Canada - National Science Library

    Artigas-Pallarés, J; Gabau-Vila, E; Guitart-Feliubadaló, M

    2005-01-01

    ..., tuberous sclerosis, Duchenne's disease, Timothy syndrome, 10p terminal deletion, Cowden syndrome, 45,X/46,XY mosaicism, Myhre syndrome, Sotos syndrome, Cohen syndrome, Goldenhar syndrome, Joubert...

  19. Edwards' syndrome.

    Science.gov (United States)

    Crawford, Doreen; Dearmun, Annette

    2016-12-08

    Edwards' syndrome is a serious genetic condition that affects fetal cellular functions, tissue development and organogenesis. Most infants with the syndrome are female, but there is no race predominance.

  20. Dravet Syndrome

    Science.gov (United States)

    ... Craniosynostosis Information Page Creutzfeldt-Jakob Disease Information Page Cushing's Syndrome Information Page Dandy-Walker Syndrome Information Page Deep Brain Stimulation for Parkinson's Disease Information Page Dementia Information ...

  1. Paraneoplastic Syndromes

    Science.gov (United States)

    ... dementia, seizures, sensory loss in the limbs, and vertigo or dizziness. Paraneoplastic syndromes include Lambert-Eaton myasthenic ... dementia, seizures, sensory loss in the limbs, and vertigo or dizziness. Paraneoplastic syndromes include Lambert-Eaton myasthenic ...

  2. 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 ...

  3. 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 ... cause your body to make too much cortisol. Cushing's syndrome is rare. Some symptoms are Upper body obesity ...

  4. Lynch Syndrome

    Science.gov (United States)

    ... colon cancer may include surgery, chemotherapy and radiation therapy. Cancer screening for people with Lynch syndrome If you ... et al. Milestones of Lynch syndrome: 1895-2015. Nature Reviews Cancer. http://www.nature.com/nrc/journal/vaop/ncurrent/ ...

  5. Metabolic Syndrome

    Science.gov (United States)

    Metabolic syndrome is a group of conditions that put you at risk for heart disease and diabetes. These ... doctors agree on the definition or cause of metabolic syndrome. The cause might be insulin resistance. Insulin is ...

  6. Meckel syndrome

    National Research Council Canada - National Science Library

    Salonen, R; Paavola, P

    1998-01-01

    Meckel syndrome (MKS) is a lethal syndrome with a central nervous system malformation, usually occipital meningoencephalocele, bilaterally large multicystic kidneys with fibrotic changes of the liver, and polydactyly in most cases...

  7. Angelman Syndrome

    Science.gov (United States)

    ... this syndrome often display hyperactivity, small head size, sleep disorders, and movement and balance disorders that can cause ... this syndrome often display hyperactivity, small head size, sleep disorders, and movement and balance disorders that can cause ...

  8. Apert Syndrome.

    Science.gov (United States)

    Datta, Saikat; Saha, Sandip; Kar, Arnab; Mondal, Souvonik; Basu, Syamantak

    2014-09-01

    Apert syndrome is one of the craniosynostosis syndromes which, due to its association with other skeletal anomalies, is also known as acrocephalosyndactyly. It is a rare congenital anomaly which stands out from other craniosynostosis due to its characteristic skeletal presentations.

  9. OAS/PKR Pathways and α/β TCR+ T Cells are Required for Ad: IFN-γ Inhibition of HSV-1 in Cornea1

    Science.gov (United States)

    Austin, Bobbie Ann; Halford, William P.; Williams, Bryan R. G.; Carr, Daniel J. J.

    2007-01-01

    An adenoviral vector containing the muIFN-γ transgene (Ad:IFN-γ) was evaluated for its capacity to inhibit HSV-1. To measure effectiveness, viral titers were analyzed in cornea and trigeminal ganglia (TG) during acute ocular HSV-1 infection. Ad: IFN-γ potently suppressed HSV-1 replication in a dose-dependent fashion, requiring IFN-γ R. Moreover, Ad:IFN-γ was effective when delivered -72 and -24 h prior to infection as well as 24 h post infection. Associated with anti-viral opposition, TG from Ad: IFN-γ transduced mice harbored fewer T cells. Also related to T cell involvement, Ad:IFN-γ was effective but attenuated in TG from α/β TCR deficient mice. In corneas, α/β TCR+ T cells were obligatory for protection against viral multiplication. Type I IFN involvement amid anti-viral efficacy of Ad: IFN-γ was further investigated because type I and II IFN pathways have synergistic anti-HSV-1 activity. Ad:IFN-γ inhibited viral reproduction in corneas and TG from IFN-α/β R deficient (CD118 −/−) mice, although viral titers were 2–3 fold higher in cornea and TG, compared to wild type. The absence of IFN-stimulated anti-viral proteins, 2’-5’ oligoadenylate synthetase/RNase L and ds RNA dependent protein kinase R, completely eliminated the anti-viral effectiveness of Ad:IFN-γ. Collectively, the results demonstrate: (1) nonexistence of type I IFN R does not abolish defense of Ad:IFN-γ against HSV-1; (2) anti-viral pathways, OAS/RNase L and PKR are mandatory; and (3) α/β TCR+ T cells are compulsory for Ad: IFN-γ effectiveness against HSV-1 in cornea but not in TG. PMID:17404299

  10. Learning about Down Syndrome

    Science.gov (United States)

    ... genetic terms used on this page Learning About Down Syndrome What is Down syndrome? What are the symptoms ... syndrome Additional Resources for Down Syndrome What is Down syndrome? Down syndrome is a chromosomal condition related to ...

  11. Germline mosaicism at the fragile X locus

    Energy Technology Data Exchange (ETDEWEB)

    Papp, A.C.; Snyder, P.J.; Sedra, M.S. [Ohio State Univ., Columbus, OH (United States)] [and others

    1994-09-01

    The fragile X full mutation, which is associated with the phenotypic expression of the disorder, is characterized by an expansion of CGG repeat and hypermethylation of the CpG island adjacent to the FMR1 gene. New mutations leading to amplification of the CGG repeat have not been reported. We have identified a fragile X syndrome pedigree where the disorder is associated with a molecular deletion. The deletion was present in the DNA of two affected sons but was absent in the mother`s somatic cell (lymphocyte) DNA. This was confirmed by dosage analysis of the Southern blot using StB12-3 and an additional probe against the dystrophin gene and by PCR analysis of DXS548 alleles. The results are consistent with the deletion arising as a postzygotic event in the mother, who therefore is germinally mosaic. The case reported here clearly demonstrates that FMR1 deletions, unlike the expansions, are not always inherited and the finding of heterozygosity or normal dosage from lymphocyte DNA in the mother of a deletion case does not necessarily rule out the possibility of having a second affected child. The deletion of FMR1 gene may be responsible for a small but significant number of fragile X cases. Therefore, it is imperative that those involved in genetic counseling recognize this diagnostic pitfall. Since it depends upon the size of the mutant clone in the mosaic mother, the exact recurrence risk in germline carriers is unknown. However, prenatal and carrier testing should be performed independently of the outcome of the mother. Furthermore, it is possible that the deletion may not be restricted to the germline, and therefore the mother may actually be a somatic mosaic.

  12. Effect of torsional mode phacoemulsification on cornea in eyes with/without pseudoexfoliation

    Institute of Scientific and Technical Information of China (English)

    Süleyman; Demircan; Mustafa; Atas; Yusufcan; Yurtsever

    2015-01-01

    AIM: To evaluate the effect of torsional mode phacoemulsification on central corneal thickness, corneal endothelial cell density, and morphology in eyes with/without pseudoexfoliation(PEX) syndrome.METHODS: Fourty-two consecutive patients with and42 patients without PEX as a control group scheduled for cataract surgery was studied. Phacoemulsification, using OZi L IP system, was performed with quick chop technique. Using noncontact specular microscopy, the central endothelial cell density(ECD), coefficient of variation, percentage of hexagonal cells, and the central corneal thickness(CCT) were evaluated preoperatively and postoperatively at 1, 7 and 30 d.RESULTS: The ECD in PEX syndrome was statistically significantly lower than that in the control group preoperatively and postoperatively(P ≤0.001).Percentage change in ECD was statistically significantly higher in PEX than that in control group after surgery follow up(P ≤0.04).There was no statistically significant difference between both groups comparing percentage of hexagonal cells and coefficient of variation in the cell size before and after the surgery. At 1 and 7d after surgery, percentage change in CCT was statistically significantly higher in PEX group than that in the control group(P ≤0.041).CONCLUSION: Although torsional mode phacoemulsification and intraocular lens(IOL) implantation provided a safe and favorable surgical outcome in patients with/without PEX, torsional phacoemulsification led to significantly higher ECD loss in the PEX group than that in the control group during the whole follow up period.In addition, more corneal swelling in the PEX group than that in the control group during the early postoperative period has indicated that the corneal endothelium, in presence of PEX endotheliopathy, seems to be more susceptible to the effects of phacoemulsification surgeryin eyes with PEX. The increased risk of anterior chamber manipulations in patients with PEX should be taken into account for

  13. History of the discovery of a master locus producing piRNAs: the flamenco/COM locus in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Coline eGoriaux

    2014-08-01

    Full Text Available The discovery of transposable elements (TEs in the 1950s by B. McClintock implied the existence of cellular regulatory systems controlling TE activity. The discovery of flam an heterochromatic locus from Drosophila melanogaster and its ability to survey several TEs such as gypsy, ZAM and Idefix contributed to peer deeply into the mechanisms of the genetic and epigenetic regulation of TEs. flam was the first cluster producing small RNAs to be discovered long before RNAi pathways were identified in 1998. As a result of the detailed genetic analyses performed by certain laboratories and of the sophisticated genetic tools they developed, this locus has played a major role in our understanding of piRNA mediated TE repression in animals. Here we review the first discovery of this locus and retrace decades of studies that led to our current understanding of the relationship between genomes and their TE targets.

  14. History of the discovery of a master locus producing piRNAs: the flamenco/COM locus in Drosophila melanogaster.

    Science.gov (United States)

    Goriaux, Coline; Théron, Emmanuelle; Brasset, Emilie; Vaury, Chantal

    2014-01-01

    The discovery of transposable elements (TEs) in the 1950s by B. McClintock implied the existence of cellular regulatory systems controlling TE activity. The discovery of flamenco (flam) an heterochromatic locus from Drosophila melanogaster and its ability to survey several TEs such as gypsy, ZAM, and Idefix contributed to peer deeply into the mechanisms of the genetic and epigenetic regulation of TEs. flam was the first cluster producing small RNAs to be discovered long before RNAi pathways were identified in 1998. As a result of the detailed genetic analyses performed by certain laboratories and of the sophisticated genetic tools they developed, this locus has played a major role in our understanding of piRNA mediated TE repression in animals. Here we review the first discovery of this locus and retrace decades of studies that led to our current understanding of the relationship between genomes and their TE targets.

  15. Velocardiofacial Syndrome

    Science.gov (United States)

    Gothelf, Doron; Frisch, Amos; Michaelovsky, Elena; Weizman, Abraham; Shprintzen, Robert J.

    2009-01-01

    Velocardiofacial syndrome (VCFS), also known as DiGeorge, conotruncal anomaly face, and Cayler syndromes, is caused by a microdeletion in the long arm of Chromosome 22. We review the history of the syndrome from the first clinical reports almost half a century ago to the current intriguing molecular findings associating genes from the…

  16. Fraser syndrome

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    Kalpana Kumari M

    2008-04-01

    Full Text Available Fraser syndrome or cryptophthalmos is a rare autosomal recessive disorder characterized by major features such as cryptophthalmos, syndactyly and abnormal genitalia. The diagnosis of this syndrome can be made on clinical examination and perinatal autopsy. We present the autopsy findings of a rare case of Fraser syndrome in a male infant.

  17. 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.

  18. Wallenberg's Syndrome

    Science.gov (United States)

    ... Information Page You are here Home » Disorders » All Disorders Wallenberg's Syndrome Information Page Wallenberg's Syndrome Information Page What ... better ways to prevent, treat, and ultimately cure disorders such as Wallenberg’s syndrome. Information from the National Library of Medicine’s ...

  19. [Dry eye syndrome in rheumatoid arthritis patients].

    Science.gov (United States)

    Polanská, V; Hlinomazová, Z; Fojtík, Z; Nemec, P

    2007-11-01

    The aim of this cross-sectional study was to review the incidence of the dry eye syndrome in rheumatoid arthritis (RA) patients, evaluate the association among the incidence of the dry eye syndrome, presence of positive rheumatoid factor (RF), the RA stage, and the duration of the disease. The group consisted of altogether 100 patients, 16 men and 84 women; the average age was 58.9 years (SD 14.6). The average duration of RA was 12.3 years, SD 11.0. In each patient, the Schirmer test I was performed, the presence of the LIPCOF (Lid Parallel Conjunctival Folds) on the slit lamp was assessed, the BUT (Tear Break-Up Time) was measured and vital fluorescein staining was performed. In each patient the data of the presence or absence of the RF in the serum, RA severity according to the X-ray examination, and the disease duration were recorded. The Pearson's association test for nominal variables was used for statistical evaluation of the association between the rheumatoid arthritis presence and the dry eye syndrome. In our group of 100 patients, the Schirmer test I was positive in 67% of patients. Positive BUT was marked in 84 % of patients. The conjunctival folds were present in 45 % of patients only. The pathological findings after cornea fluorescein staining appeared in 18 % of patients. The dry eye syndrome incidence was marked in 74% of patients with RA. Subjective difficulties were declared by 38.3% of patients only. The local treatment was already established in 23.0% of patients only. We did not find statistically significant correlation between the RF positive rheumatoid arthritis appearance and dry eye syndrome, nor between the stage of the rheumatoid arthritis and presence of the dry eye syndrome. We proved statistical connection between the presence of dry eye syndrome and the duration of rheumatoid arthritis longer than 10 years. Keratoconjunctivitis sicca is the most common ocular complication in rheumatoid arthritis patients. We proved the connection

  20. Refeeding syndrome.

    Science.gov (United States)

    Fernández López, M T; López Otero, M J; Alvarez Vázquez, P; Arias Delgado, J; Varela Correa, J J

    2009-01-01

    Refeeding syndrome is a complex syndrome that occurs as a result of reintroducing nutrition (oral, enteral or parenteral) to patients who are starved or malnourished. Patients can develop fluid-balance abnormalities, electrolyte disorders (hypophosphataemia, hypokalaemia and hypomagnesaemia), abnormal glucose metabolism and certain vitamin deficiencies. Refeeding syndrome encompasses abnormalities affecting multiple organ systems, including neurological, pulmonary, cardiac, neuromuscular and haematological functions. Pathogenic mechanisms involved in the refeeding syndrome and clinical manifestations have been reviewed. We provide suggestions for the prevention and treatment of refeeding syndrome. The most important steps are to identify patients at risk, reintroduce nutrition cautiously and correct electrolyte and vitamin deficiencies properly.