1: Invest Ophthalmol Vis Sci. 2012 Feb 1;53(2):586. Print 2012. 

Author response: bayesian estimation of sensitivity of temporal artery biopsies.

Niederkohr RD, Levin LA.

The Permanente Medical Group, Santa Clara, California;

PMID: 22298152  [PubMed - in process]

2: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Recovery of axonal transport after partial optic nerve damage is associated with
secondary retinal ganglion cell death in vivo.

Prilloff S, Henrich-Noack P, Sabel BA.

Institute of Medical Psychology, Otto-von-Guericke University of Magdeburg,
Magdeburg, Germany.

Purpose:Traumatic injury of the optic nerve leads to retrograde cell death of
retinal ganglion cells (RGCs) but usually a certain percentage of neurons
survive. It has been suggested that recovery of axonal transport is beneficial
for survival. The current study was therefore performed to provide a synopsis of
the temporal pattern of axonal transport decline/recovery and the viability of
RGCs after optic nerve crush (ONC).Methods:Fluorescent dyes were injected into
the superior colliculus to retrogradely label RGCs. Axonal transport kinetics
into the RGCs was visualized with In Vivo Confocal Neuroimaging (ICON) in
uninjured rats and in rats which had mild or moderate ONC. We injected red
fluorescent beads on day 2 post-ONC and green beads on day 7.Results:At 2-4 days
post-ONC significant axonal transport was detected, but within one week the
transport of the fluorescent beads was decreased. Interestingly, during post-ONC
weeks 3 the axon transport slowly recovered. However, despite this recovery,
retrograde cell death rate continued and was even increased in a "second wave"
of cell death in those neurons that displayed axon transport
recovery.Conclusion:Following damage many surviving RGCs lose their axon
transport, but after about 3 weeks, this transport recovers again, a sign of
intrinsic axon repair. Contrary to the prediction, axon transport recovery is
not associated with better cell survival but rather with a second wave of cell
death. Thus, the accelerated cell death associated with recovery of axon
transport suggests the existence of a late retrograde cell death signal.

PMID: 22297499  [PubMed - as supplied by publisher]

3: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Normalization of Visual Evoked Potentials Using Underlying Electroencephalogram
Levels Improves the Amplitude Reproducibility in Rats.

You Y, Thie J, Klistorner A, Gupta VK, Graham SL.

. Department of Ophthalmology, Australian School of Advanced Medicine, Macquarie
University.

Purpose:The visual evoked potential (VEP) is an important non-invasive
measurement of the visual function. However, the high amplitude variability has
limited its potential in evaluating axonal damage in both laboratory and
clinical research. This study aims to improve the reliability of VEP amplitude
measurement in rats using electroencephalogram (EEG)-based signal
correction.Methods:VEPs of Sprague-Dawley rats were recorded on three separate
days within two weeks. The original VEP traces were normalized by EEG power
spectrum, which was evaluated using Fourier transform. A comparison of
intersession reproducibility and intersubject variability was made between the
original and the corrected signals.Results:Corrected VEPs showed lower amplitude
intersession within-subject standard deviation (Sw), coefficient of variation
(CoV) and repeatability (R(95)) than the original signals (p < 0.001). The
intraclass correlation coefficient (ICC) value of the corrected traces (0.90)
was also better than the original potentials (0.82). For the intersubject
variability, the EEG-based normalization improved the intersubject CoV from
44.64% to 30.26%. A linear correlation was observed between the EEG level and
the VEP amplitude (r = 0.71, p < 0.0001).Conclusions:We recommend that
underlying EEG signals should be considered in measuring the VEP amplitude. This
study developed a useful technique for VEP data processing, which could also be
used for other cortical evoked potential recordings and for clinical VEP
interpretation in humans.

PMID: 22297498  [PubMed - as supplied by publisher]

4: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Multipotent Stem Cells from Trabecular Meshwork Become Phagocytic TM cells.

Du Y, Roh DS, Mann MM, Funderburgh ML, Funderburgh JL, Schuman JS.

UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of
Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA.

Purpose.To isolate and characterize stem cells from human trabecular meshwork
(TM) and to investigate the potential of these stem cells to differentiate into
TM cells.Methods.Human trabecular meshwork stem cells (TMSC) were isolated as
side population cells by fluorescence-activated cell sorting or isolated by
clonal cultures. Passaged TMSC were compared with primary TM cells by
immunostaining and quantitative RT-PCR. TMSC purity was assessed by flow
cytometry and TMSC multipotency was examined by induction of neural cells,
adipocytes, keratocytes or TM cells. Differential gene expression was detected
by quantitative RT-PCT, immunostaining and immunoblotting. TM cell function was
evaluated by phagocytic assay using inactivated S. aureus
bioparticles.Results.Side population and clonal isolated cells expressed stem
cell markers ABCG2, Notch1, OCT4, AnkG and MUC1 but not TM markers AQP1, MGP,
CHI3L1 or TIMP3. Passaged TMSC are a homogeneous population with more than 95%
cells positive to CD73, CD90, CD166 or Bmi1. TMSC exhibited multipotent ability
of differentiation into a variety of cell types with expression of neural
markers neurofilament, beta-tubulin III, GFAP; or keratocyte specific markers
keratan sulfate and keratocan; or adipocyte markers ap2 and Leptin. TMSC readily
differentiated into TM cells with phagocytic function and expression of TM
markers AQP1, CHI3L1 and TIMP3.Conclusions.TMSC isolated as side population or
as clones express specific stem cell markers, are homogeneous and multipotent
with the ability to differentiate into phagocytic TM cells. These cells offer a
potential for development of a novel stem cell-based therapy for glaucoma.

PMID: 22297497  [PubMed - as supplied by publisher]

5: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

TSG-6 Controls Transcription and Activation of Matrix Metalloproteinase 1 in
Conjunctivochalasis.

Guo P, Zhang SZ, He H, Zhu YT, Tseng SC.

R&D Department, TissueTech, Inc., Ocular Surface Center, and Ocular Surface
Research & Education Foundation, Miami, FL, USA;

Purpose:To investigate the role of anti-inflammatory TSG-6 in controlling MMP-1
and MMP-3 which have been shown to be upregulated in conjunctivochalasis
(CCh).Methods:Immunostaining of TSG-6 was compared between normal and CCh
conjunctiva and Tenon. Second cultures of normal and CCh fibroblasts were
transfected with or without TSG-6 siRNA followed by with or without addition of
TNF-alpha or IL-1beta. Cell lysates and culture media were collected to assess
apoptosis by the Cell Death Detection ELISA and expression of TSG-6, MMP-1 and
MMP-3 transcripts and proteins by qRT-PCR and Western blot,
respectively.Results:Expression of TSG-6 was constitutive in the in vivo normal
conjunctival epithelium. Significantly more TSG-6-positive cells were noted in
CCh subconjunctival tissue and Tenon than normal specimens. TSG-6 was
constitutively expressed intracellularly by both resting normal and CCh
fibroblasts, but secreted extracellularly only by resting CCh fibroblasts.
Intracellular and extracellular TSG-6 proteins were markedly upregulated by
TNF-alpha or IL-1beta in normal and CCh fibroblasts. Active MMP-1 was found in
CCh fibroblasts intracellularly and extracellularly, while only proMMP-1 was
found intracellularly in normal fibroblasts. Knockdown by TSG-6 siRNA
upregulated more MMP-1 than MMP-3 transcripts in normal and CCh fibroblasts.
TSG-6 siRNA led to expression extracellular MMP-1 by normal fibroblasts like CCh
fibroblasts. Such activation of MMP-1 was further enhanced by IL-1beta. Cell
apoptosis was higher in CCh fibroblasts and further aggravated by TSG-6 siRNA
knockdown.Conclusions:TSG-6 exerts an anti-inflammatory function by
counteracting transcription of MMP-1 and MMP-3 as well as activation of MMP-1.
Dysfunction of TSG-6 might play a role in pathogenesis of CCh.

PMID: 22297496  [PubMed - as supplied by publisher]

6: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Nintendo Wii Remote Controllers for Head Posture Measurement: Accuracy, Validity
and Reliability of Infrared Optical Head Tracker.

Kim J, Nam KW, Jang IG, Yang HK, Kim KG, Hwang JM.

Department of Ophthalmology, Seoul National University College of Medicine,
Seoul, Korea.

Purpose:To evaluate the accuracy, validity, and reliability of a newly-developed
infrared optical head tracker (IOHT) using Nintendo Wii remote controllers
(WiiMote; Nintendo Co. Ltd., Kyoto, Japan) for measurement of the angle of head
posture.Methods:IOHT consists of two infrared (IR) receivers (WiiMote) that are
fixed to a mechanical frame and connected to a monitoring computer via Bluetooth
communication channel, and an IR beacon that consists of four IR light-emitting
diodes (LEDs). Using a cervical range of motion (CROM; Performance Attainment
Associates, St. Paul, MN, USA) as a reference, one- and three-dimensional (1-D
and 3-D) head postures of 20 normal adult subjects (20 to 37 years old, 9
females and 11 males) were recorded with IOHT.Results:In comparison with the
data from CROM, IOHT-derived results showed high consistency. The measurements
of 1-D and 3-D positions of human head with IOHT were very close to those of
CROM. The correlation coefficients of 1-D and 3-D positions between IOHT and
CROM were more than 0.99 and 0.96 (P value < .05, Pearson's correlation test),
respectively. Reliability tests of IOHT for the normal adult subjects for 1-D
and 3-D positions of human head had 95% limits of agreement angles, about +/-4.5
degrees  and +/-8.0 degrees , respectively.Conclusion:IOHT showed strong
concordance with CROM and relatively good test-retest reliability, thus proving
its validity and reliability as a head posture measuring device. Considering its
high performance, ease of use, and low cost, we believe IOHT has the potential
to be widely used as a head posture measuring device in clinical practice.

PMID: 22297495  [PubMed - as supplied by publisher]

7: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Effect of corneal stiffening on Goldmann Applanation Tonometry and Tonopen
measurements in canine eyes.

Tang J, Pan X, Weber PA, Liu J.

Department of Biomedical Engineering, Ohio State University.

Purpose:To experimentally examine the effect of increased corneal stiffness on
Goldmann Applanation Tonometry (GAT) and Tonopen measurements of intraocular
pressure (IOP) in a canine eye model.Methods:Twenty globes were recovered from
ten dogs with no known diseases. For each dog, corneal stiffening was induced in
one eye with glutaraldehyde/PBS (phosphate buffered saline) immersion while the
other cornea was immersed in PBS only. Acoustic impedance was measured before
and after treatment in all eyes. After treatment, IOP was measured by GAT and
Tonopen at true pressures of 10, 15, 20, 30, and 40 mmHg. The corneas were then
dissected for uniaxial tensile testing. The GAT/Tonopen readings, corneal
stiffness (measured by ultrasound and tensile tests), and corneal thickness were
compared between the two groups. The correlations between GAT/Tonopen readings
and corneal stiffness were evaluated.Results:Acoustic impedance significantly
increased after glutaraldehyde treatment (p<0.01). Secant modulus at 1% strain
was significantly higher in corneas treated with glutaradehyde/PBS than those
treated with PBS only (p<0.01). GAT and Tonopen readings were significantly
higher at all pressure levels (p<0.001) in the eyes with corneal stiffening.
Both corneal acoustic impedance and secant modulus were significantly correlated
with GAT/Tonopen readings at all pressure levels (p<0.01).Conclusions:This study
provided experimental evidence that corneal stiffening significantly increases
GAT and Tonopen readings in canine eyes. Noninvasive ultrasound measurement of
acoustic impedance may be used to evaluate corneal stiffness and improve the
accuracy of clinical measurements of IOP.

PMID: 22297494  [PubMed - as supplied by publisher]

8: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Corneal surface asphericity, roughness, and transverse contraction following
uniform scanning excimer laser ablation.

McCafferty SJ, Schwiegerling JT, Enikov ET.

Purpose:Examine the interaction between the excimer laser and residual
tissue.Methods:Ten (10) cadaveric porcine eyes with exposed corneal stroma and
plastic test spheres underwent uniform 6mm ablation using a Visx S4 scanning
excimer laser. Corneal profilometry of the central 3mm was measured with
sub-micron resolution optical interferometry before and after uniform excimer
ablation. Eleven (11) surface marked eyes were photomicrographed before and
after excimer ablation. Images were superimposed and mark positional changes
were measured.Results:Uniform scanning excimer laser ablation to corneal stroma
produces a significant central steepening and peripheral flattening in the
central 3mm diameter. The central 1mm corneal curvature radius decreased from
r=10.07+/-0.44mm(95%CI) to 7.22+/-0.30mm and the central 2mm radius decreased
from r=10.16+/-0.44mm to r=8.10+/-0.43mm. Q-values, measuring asphericity in the
central 2mm of the cornea, were significantly lower pre-ablation than post
ablation (-5.03+/-4.01vs.-52.4+/-18.7,respectively). Surface roughness increased
significantly from 0.65+/-0.06microns to 1.75+/-0.32microns following ablation.
The central 2mm of the stromal surface contracted by 2.21%+/-0.80% at a
sustained temperature of 5 degrees C. Ablation of plastic spheres produced no
significant changes.Conclusions: The excimer laser interacts with the unablated
residual stromal surface in a characteristic fashion not seen with isotropic,
inorganic material. Increases in asphericity, surface roughness, surface
contraction, and stromal morphological changes are supportive of this
interaction. The surface changes demonstrated may be indicative of temperature
induced transverse collagen fibril contraction and stress re-distribution or the
ablation threshold of the stromal surface may be altered . This phenomenon may
be of increased importance utilizing lasers with increased thermal load.

PMID: 22297493  [PubMed - as supplied by publisher]

9: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Suppression of type I collagen expression by miR-29b via PI3K, Akt, and Sp1
pathway in Human Tenon's Fibroblasts.

Li N, Cui J, Duan X, Chen H, Fan F.

Department of Ophthalmology, Second Xiangya Hospital, Central South University,
Changsha 410000, Hunan Province, P.R.China.

Purpose.To evaluate the expression profile of microRNAs (miRNAs) and their roles
in human tenon's fibroblasts (HTFs), and to establish a miRNA-based gene
silencing method for antifibrosis in vitro.Methods.The miRNA expression profile
was analyzed by microarray using quiescent and TGFbeta1-stimulated primary HTFs,
respectively. Candidate miRNAs were identified by quantitative RT-PCR. miRNAs
potentially targeting fibrosis-related genes were predicted using a published
algorithm (TargetScan; Envisioneering Medical Technologies, St. Louis, MO).
Predicted fibrosis-related genes regulated by candidate miRNAs were confirmed by
transfection of the miRNA into HTF culture (with or without TGFbeta1 treatment),
followed by quantitative RT-PCR and Western Blot.Results.Total of 38 miRNAs were
identified to be upregulated, and 31 down-regulated, in TGFbeta1-stimulated
HTFs. Among those, the miR-29b, down-regulated in TGFbeta1-treated HTFs,
targeted a cadre of mRNAs that encode proteins involved in fibrosis, including
PI3Kp85a, Sp1, and collagen type I alpha1 (Col1A1). Treatment of HTFs with
TGFbeta1 activated the PI3K-Akt-Sp1 pathway and, consequently, induced7 an
increase in the expression of type I collagen. Down-regulation of miR-29b by
introducing an antisense miRNA into cultured HTFs partly induced the expression
of PI3Kp85a, Akt, Sp1 and Col1A1, whereas overexpression of miR-29b inhibited
the PI3K-Akt-Sp1 pathway and attenuated the expression of
Col1A1.Conclusions.miR-29b acted as a suppressor of type I collagen gene by
repressing the PI3K/Akt/Sp1 pathway in HTFs. Overexpression of miR-29b protected
subconjunctival tissues against collagen production and fibrosis. These findings
provided a novel rationale for the development of miRNA-based strategies for
attenuating scar formation after glaucoma filtering surgery.

PMID: 22297492  [PubMed - as supplied by publisher]

10: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Automated Assessment of Drusen Using Three-dimensional Spectral-domain Optical
Coherence Tomography.

Iwama D, Hangai M, Ooto S, Sakamoto A, Nakanishi H, Fujimura T, Domalpally A,
Danis RP, Yoshimura N.

Department of Ophthalmology and Visual Sciences, Kyoto University Graduate
School of Medicine, Kyoto, Japan.

Purpose:To compare automated assessment of macular drusen delineated by our
originally-developed algorithm on 3-dimensional (3D) spectral-domain optical
coherence tomography (SD-OCT) with the assessment by certificated graders on
color fundus photographs in non-neovascular age-related macular degeneration
(AMD).Design:Prospective case series.Methods:Automated assessment of macular
drusen was performed using raster scan by 3D OCT-1000 (Topcon) in 18 eyes with
non-neovascular AMD with at least one large druse (>/=125mum) and predominantly
soft indistinct drusen. We defined drusen as the regions that have the distance
between the RPE and calculated Bruch's membrane lines > predefined threshold
distances. We assessed the agreement on maximum drusen size and drusen area
within grid between 3D SD-OCT and color fundus photographs, and false-negative,
and false-positive drusen at each threshold distance.Results:There was agreement
or agreement within one step in all eyes in maximum drusen size, and 15 (83.3%)
of the eyes in drusen area, except 6 pixels, regardless of threshold distances.
However, the number of eyes with exact agreement in drusen area increased when
the threshold distances were smaller than 4 pixels. In the 3 cases with
disagreement in drusen area, false-negative drusen on 3D SD-OCT were
characterized by being small in area and height.Conclusion:Automated assessment
of drusen parameters based on our algorithm on 3D SD-OCT, which was limited by
the poor detection ability of small drusen, showed good agreement with the
assessment by certified graders on color fundus photography in our subjects.

PMID: 22297491  [PubMed - as supplied by publisher]

11: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Differentiation between Infectious and Non-infectious Ulcerative Keratitis by
Raman Spectra of Human Teardrops: A Pilot Study.

Kuo MT, Lin CC, Liu HY, Yang MY, Chang HC.

. Department of Biomedical Engineering, National Cheng Kung University, Tainan,
Taiwan.

PurposeThe aim of this study was to use Raman spectra of tears to differentiate
between infectious and non-infectious ulcerative keratitis.MethodsWe applied
Raman microspectroscopy using the drop-coating deposition method on Ti/Au-coated
glass slides to obtain sample spectra from different human tear groups,
including tears from normal subjects and patients with infectious and
non-infectious ulcerative keratitis. By comparing the difference spectra from
the groups, we identified local Raman features useful for differentiation of
ulcerative keratitis. Principle components (PCs) of normal tears were used as
affined spectral coordinates. After performing projections of Raman spectra of
both infectious and non-infectious tear samples, we compared the 2 groups to
identify global spectral parameters with differential statistical
significance.ResultsThe differentiation between IUK and NIUK might be directly
made through observation of the normalized tear Raman spectra or the transformed
principle scores. The spectral segments with differential statistical
significance included 878 approximately 888 cm(-1), 885 approximately 888
cm(-1), 945 approximately 993 cm(-1), 1007 approximately 1015 cm(-1), 1074
approximately 1100 cm(-1),() 1090 approximately 1094 cm(-1),() 1096
approximately 1099 cm(-1),() 1386 approximately 1403 cm(-1), 1463 approximately
1469 cm(-1), 1469 approximately 1473 cm(-1), 1557 approximately 1563 cm(-1),
1584 approximately 1588 cm(-1), and 1614 approximately 1621 cm(-1). There were 2
PCs with statistically significant differences for the 2 groups of ulcerative
keratitis, including PC1 (p = 0.01) and PC2 (p = 0.05).ConclusionsThis novel
approach using the analysis of Raman spectra of teardrop samples for
differentiation of ulcerative keratitis demonstrates the potential application
of Raman microspectroscopy for clinical practice. This technology should
complement the conventional cytological method for rapid diagnosis in the
clinician's office.

PMID: 22297490  [PubMed - as supplied by publisher]

12: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

In vivo Assessment of Anti-microbial Efficacy of Silver-impregnated Contact Lens
Storage Cases.

Dantam J, Zhu H, Willcox M, Ozkan J, Naduvilath T, Thomas V, Stapleton F.

Brien Holden Vision Institute, Sydney, Australia.

Purpose:To evaluate microbial contamination in silver-impregnated contact lens
(CL) storage cases, while establishing the effect of 'wet' and 'dry' case
maintenance and to determine its association with clinical signs, symptoms and
compliance.Methods:Two non-contemporaneous prospective studies were conducted.
Regular storage cases in study I (n = 40) and silver-impregnated cases in study
II (n = 41) were used in conjunction with AQuify((R)) and CLs (Balafilcon A).
Cases were replaced monthly and collected at 1, 3 and 4 (for silver-impregnated
cases only) months. Regular cases and the 4(th) month silver-impregnated cases
were maintained 'dry' and other cases were maintained 'wet' between uses. At
collection, storage cases were sampled and cultured for microbial identification
and enumeration. Ocular clinical findings, subjective responses to CL wear and
compliance were recorded at each visit.Results:The percentage of microbial
contamination for silver-impregnated and regular cases was 71% and 82%
respectively. There were significantly (p<0.005) fewer organisms in
silver-impregnated cases (1.7 log CFU per well) compared to regular cases (4.1
log CFU per well). In particular, silver-impregnated cases showed lower levels
of Gram-negative bacteria (p=0.04), Gram-positive bacilli (p=0.03) and fungi
(p=0.006). Maintaining the silver-impregnated cases 'wet' resulted in lower
percentage of contamination (71%; p<0.01) than maintained 'dry' (94%). There was
no association between any clinical signs, symptoms and compliance and microbial
contamination of storage cases.Conclusions:More than 70% of the storage cases
used in daily wear CL care for a month was contaminated irrespective of the
types of cases. However, silver-impregnated cases were colonised by reduced
levels of Gram negative bacteria.

PMID: 22297489  [PubMed - as supplied by publisher]

13: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Silencing of Fem1cR3 gene expression in the DBA/2J mouse precedes retinal
ganglion cell death and is associated with Histone Deacetylase activity.

Pelzel HR, Schlamp CL, Waclawski M, Shaw MK, Nickells RW.

Department of Ophthalmology and Visual Sciences, University of Wisconsin,
Madison, WI 53706.

Purpose.Down-regulation of normal gene expression in dying retinal ganglion
cells has been documented in both acute and chronic models of optic nerve
disease. We examined the mechanism and timing of this phenomenon in DBA/2J mice,
using genetically modified substrains of this inbred line.Methods.DBA/2J mice,
doubly congenic for the Bax mutant allele and the ganglion cell reporter gene
Fem1c(Rosa3) (R3), were evaluated to elucidate the timing of loss of normal gene
expression during the apoptotic process. The localization of Histone Deacetylase
3 (HDAC3) and nuclear histone H4 acetylation were examined by immunofluorescence
in dying cells. The role of HDACs in gene silencing during glaucoma was
interrogated using the global HDAC inhibitor Trichostatin A
(TSA).Results.Silencing of the R3 allele occurred in Bax(-/-) ganglion cells,
indicating that this process preceded the committed step of the intrinsic
apoptotic pathway. Weekly TSA treatment, between the ages of 6 and 10 months,
was able to attenuate the loss of R3 expression in the retina, but had no effect
on optic nerve degeneration. Dying cells in aging DBA/2J mice exhibited nuclear
localization of HDAC3 and a decrease in the level of H4
acetylation.Conclusions.Retinal ganglion cells exhibit a loss of normal gene
expression as an early (pre BAX involvement) part of their apoptotic program
during glaucomatous degeneration. This process can be ameliorated, but not
completely blocked, using HDAC inhibitors. Epigenetic changes to active
chromatin, such as deacetylation, may be mediated by HDAC3 in dying neurons.

PMID: 22297488  [PubMed - as supplied by publisher]

14: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Changes in murine hyalocytes are valuable early indicators of ocular disease.

Vagaja NN, Chinnery HR, Binz N, Kezic JM, Rakoczy EP, McMenamin PG.

Anatomy and Developmental Biology, School of Biomedical Sciences, Monash
University, Clayton, VIC 3800.

Background:The present study examined the distribution, density and phenotype of
hyalocytes or vitreous macrophages in mouse eyes during normal ageing and in
models of background diabetic retinopathy, retinal vascular proliferation and
exposure to TLR4 and 9 ligands.Materials and Methods:The phenotype and density
of hyalocytes were investigated in retinal and ciliary body whole mounts of
normal wild type (WT) (C57BL/6) mice at 7, 17 and 120 weeks of age, Ins2(Akita)
mice, transgenic Kimba mice (VEGF-induced retinal neovascularisation) and in WT
mice 24 hours following single intraperitoneal lipopolysaccharide (LPS) with LPS
(9mug/g body weight) or 1 week following three fortnightly identical doses. A
further group of mice received a single topical drop of 20mug of
CpG-oligodeoxynucleotides (CpG-ODN) to the abraded corneal surface and were
sacrificed 1 week later.Results:The data revealed an approximately 5-fold
increase in density of preretinal hyalocytes in 120 week old mice. Some
hyalocytes contained phagocytosed melanin. Hyalocyte density was doubled in
Ins2(Akita) mice after only 3-4 weeks of hyperglycaemia. Kimba mice had 8-fold
increase in density of hyalocytes and many displayed signs of activation. WT
mice exposed to single or multiple systemic doses of LPS showed a 2-3-fold
increase in hyalocyte. Topical CpG-ODN treatment led to a very marked (7-fold)
increase in preretinal hyalocytes density.Conclusion:The present study
demonstrated that murine hyalocytes were responsive to aging, hyperglycaemia,
locally produced VEGF and both systemic and ocular-derived TLR ligands. Thus
hyalocytes or vitreous macrophages may be a valuable and previously unrecognised
sensitive indicator of pathological changes in the eye.

PMID: 22297487  [PubMed - as supplied by publisher]

15: Invest Ophthalmol Vis Sci. 2012 Feb 1; [Epub ahead of print] 

Planimetrically Determined Vertical Cup/Disc and Rim Width/Disc Diameter Ratios
and Related Factors.

Tsutsumi T, Tomidokoro A, Araie M, Iwase A, Sakai H, Sawaguchi S.

Department of Ophthalmology, University of Tokyo Graduate School of Medicine,
Tokyo, Japan;

Purpose.To evaluate the distribution and factors related to planimetrically
determined vertical cup/disc (v-C/D) and rim width/disc diameter (Rw/Dd) ratios
of the optic discs in a population-based study of Japanese subjects without
glaucoma.Methods.Of 4,632 eligible residents aged 40 years and older, 3,762
residents underwent a detailed ocular examination including sequential optic
disc stereo photography with a digital non-mydriatic fundus camera. The
photographs were assessed by computer-assisted planimetry. We studied both eyes
of 2,311 subjects and only one right (left) eye of 196 (175) non-glaucomatous
subjects for whom disc stereo photographs of acceptable quality.Results.The
median (2.5(th) and/or 97.5(th) percentile) disc area, v-C/D, its asymmetry, and
the superior- and inferior-minimal Rw/Dd ratios were 2.56 (1.68, 3.71) mm(2),
0.56 (0.70), 0.05 (0.14), 0.18 (0.10) and 0.21 (0.12), respectively. Multiple
regression analysis showed that men had larger discs and superior Rw/Dd and
smaller inferior Rw/Dd ratios. Increased age was correlated with increased v-C/D
and decreased superior and inferior Rw/Dd ratios. Higher intraocular pressure
(IOP) and thinner central corneal thickness (CCT) were correlated with higher
v-C/D and smaller inferior rim/disc ratios, and lower diastolic ocular perfusion
pressure (OPP) with greater v-C/D and smaller superior Rw/Dd
ratios.Conclusions.In non-glaucomatous eyes, increased v-C/D and decreased
superior and inferior Rw/Dd ratios were significantly correlated not only with
increased age and disc size but also with higher IOP, lower diastolic OPP, and
thinner CCT, suggesting that these simple disc parameters also represent
vulnerability to glaucoma insults in non-glaucomatous eyes.

PMID: 22297486  [PubMed - as supplied by publisher]

16: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

Cysteamine prevents the development of lens opacity in a rat model of
selenite-induced cataract.

Lee SM, Jeong EM, Jeong J, Shin DM, Lee HJ, Kim HJ, Lim J, Lee JH, Cho SY, Kim
MK, Wee WR, Lee JH, Kim IG.

Department of Ophthalmology, Seoul National University College of Medicine,
Seoul, Korea.

Purpose:The activation of transglutaminase 2 (TG2) by oxidative stress through
TGFbeta has been reported to play a crucial role in cataract formation. We
investigated whether TG2 is involved in selenite-induced cataract formation in
rats and whether cysteamine, a chemical inhibitor of TG2, can prevent cataract
formation in this model.Methods:Intracellular TG2 activity was monitored in a
human lens epithelial cell (HLE-B3) line and cultured rat lenses after treatment
with selenite. Rat pups (13 days old) were injected with sodium selenite
(Na(2)SeO(3); 20 micromol/kg) subcutaneously together with the intraperitoneal
administration of cysteamine (30, 40, and 60 mg/kg) for 14 days. Lenses were
evaluated photographically at days 7 and 14. The concentrations of
malondialdehyde and glutathione in the lenses were determined.Results:In HLE-B3
cells or rat lenses, selenite induced intracellular TG activity, which was
inhibited by cysteamine. In selenite-treated rats, the rate of cataract
formation was significantly reduced by cysteamine (P < 0.001). The mean cataract
area in the lenses of cysteamine-treated rats was smaller than that of control
rats (P < 0.01). The levels of total and reduced glutathione in the lenses of
cysteamine-treated rats extracted at day 14 were higher than those of control
rats.Conclusion:Cysteamine suppresses cataract formation induced by selenite in
rats, suggesting that cysteamine could be used as a pharmaceutical intervention
to prevent or delay cataract formation.

PMID: 22281827  [PubMed - as supplied by publisher]

17: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

Assessment of Differential Pharmacodynamic Effects using Optical Coherence
Tomography in Neovascular Age-Related Macular Degeneration.

Keane PA, Heussen FM, Ouyang Y, Mokwa N, Walsh AC, Tufail A, Sadda SR, Patel PJ.

NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS
Foundation Trust and UCL Institute of Ophthalmology.

Purpose:To assess the differential pharmacodynamic effects of bevacizumab
(Avastin), pegaptanib (Macugen), and verteporfin photodynamic therapy (PDT),
using novel OCT parameters, in a recently completed phase III/IV clinical
trial.Methods:Data from 122 patients participating in the Avastin (Bevacizumab)
for Choroidal neovascularization (ABC) trial, were evaluated. Stratus OCT images
were analyzed using custom software - changes in volume of the neurosensory
retina, subretinal fluid (SRF), pigment epithelium detachment (PED), and
subretinal tissue, were calculated over the 54-week trial
period.Results:Reductions in retinal oedema were more than twice as great from
bevacizumab than pegaptanib (-0.82 mm(3) versus -0.31 mm(3)), while SRF
reduction was more than three times greater (-0.54 mm(3) versus -0.15 mm(3)).
Both bevacizumab and pegaptanib led to rapid reductions in subretinal tissue;
however, in those receiving pegaptanib, these improvements were not maintained
(at week 54: -0.22 mm(3) versus +0.18 mm(3)). Acute increases in SRF were seen
one week after PDT (+0.36 mm(3)) and, across all treatment groups, PED volume
tended to remain unchanged, or regress only slowly.Conclusions:In clinical
trials, quantitative OCT subanalysis increases the amount of clinically useful
information that can be obtained from OCT images. In the emerging era of
neovascular AMD therapeutics, the capacity of OCT to provide such detailed
pharmacodynamic information, in a non-invasive manner, is likely to attain
increased importance. In future comparative studies, evaluation of subretinal
tissue may highlight differential effects on vascular proliferation, while
measurement of PED volume may prove useful for the estimation of retinal and
sub-retinal pigment epithelium (RPE) therapeutic penetration.

PMID: 22281826  [PubMed - as supplied by publisher]

18: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

Thy1 Associates with the Cation Channel Subunit HCN4 in Adult Rat Retina.

Partida GJ, Stradleigh TW, Ogata G, Godzdanker I, Ishida AT.

Section of Neurobiology, Physiology and Behavior.

Purpose:The membrane expression and gene promoter of the
glycosylphosphatidylinositol (GPI)-anchored protein Thy1 have been widely used
to examine the morphology and distribution of retinal ganglion cells in normal
eyes and disease models. However, it is not known how adult mammalian retinal
neurons utilize Thy1. Because Thy1 is not a membrane-spanning protein and,
instead, complexes with structural and signaling proteins in other tissues, the
aim of this study was to find protein partners of retinal
Thy1.Methods:Coimmunoprecipitation, immunohistochemistry, confocal imaging, and
patch-clamp recording were used to test for association of Thy1 and HCN4, a
cation channel subunit, in adult rat retina.Results:Hyperpolarization of cells
immunopanned by an anti-Thy1 antibody activated HCN channels. Confocal imaging
showed that individual somata in the ganglion cell layer bound antibodies
against Thy1 and HCN4, that the majority of these bindings colocalized, and that
some of the immunopositive cells also bound antibody against a ganglion cell
marker (Brn3a). Consistent with these results, Thy1 and HCN4 were
coimmunoprecipitated by magnetic beads coated with either anti-Thy1 antibody or
anti-HCN4 antibody. In control experiments, beads coated with these antibodies
did not immunoprecipitate a photoreceptor rim protein (ABCR) and uncoated beads
did not immunoprecipitate either Thy1 or HCN4.Conclusions:This is the first
report that Thy1 colocalizes and coimmunoprecipitates with a membrane-spanning
protein in retina, that Thy1 complexes with an ion channel protein in any
tissue, and that a GPI-anchored protein associates with an HCN channel subunit
protein.

PMID: 22281825  [PubMed - as supplied by publisher]

19: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

Corneal and conjunctival sensory function: the impact on ocular surface
sensitivity of change from low to high oxygen transmissibility contact lenses.

Golebiowski B, Papas EB, Stapleton F.

School of Optometry and Vision Science, The University of New South Wales.

PurposeDeprivation of oxygen to the ocular surface during contact lens wear has
been implicated in the alteration of sensory function. This study investigates
whether increasing oxygen availability through discontinuation of contact lens
wear or transfer into highly oxygen transmissible (high Dk/t) lenses leads to a
change in corneal or conjunctival sensitivity.MethodsTwenty-seven long-term
extended wearers of low Dk/t soft contact lenses ceased lens wear for 1 week and
were refitted with high Dk/t silicone hydrogel lenses. A control group of 25
non-wearers matched for age and gender was also recruited. Central corneal and
inferior conjunctival sensitivity was measured using the CRCERT-Belmonte
Aesthesiometer. Threshold was determined using a staircase technique.
Measurements were taken during low Dk/t lens wear, after 1 week of no wear and
following 1, 3, 6 and 12 months of high Dk/t lens wear. Measurements were
carried out on one occasion on the non-wearers.ResultsCorneal sensitivity
decreased 1 week after discontinuation of low Dk/t lenses and no further change
in sensitivity occurred with high Dk/t lens wear. Conjunctival sensitivity did
not change over the same time-frame. Ocular surface sensitivity in long-term low
Dk/t soft lens wearers was similar to non-wearers. Sensitivity was higher in
females than males in the non-wearers, but not in the lens wearing group. An
interaction of gender on change in conjunctival threshold was found in the lens
wearers.ConclusionsThese findings indicate that factors other than oxygen
availability alone determine sensitivity of the ocular surface. Slicone hydrogel
contact lenses appear to have only a minor impact on ocular surface sensitivity
in previous lens wearers.

PMID: 22281824  [PubMed - as supplied by publisher]

20: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

VISUAL ACUITY IS REDUCED IN alphaLPHA 7 NICOTINIC RECEPTOR KNOCK-OUT MICE.

Origlia N, Valenzano DR, Moretti M, Gotti C, Domenici L.

Neuroscience Institute (National Council of Research, C.N.R.), Pisa, Italy;

Purpose.Nicotinic receptors (nAChRs) are part of a heterogeneous family of
pentameric ligand-gated ion channels that are widely expressed in the visual
system. We investigated the impact of alpha7 homomeric nAChRs on visual function
using mutant mice lacking the alpha7 nicotinic receptor subunit.Methods.We
measured spatial resolution limit in alpha7 knock-out (alpha7 KO) and
age-matched control mice using three independent methods: an operant behavioral
visual task (Prusky maze), cortical visual evoked potentials (VEPs), and the
pattern electroretinogram (PERG) evoked by alternating gratings of different
spatial frequencies and contrasts.Results.Visual acuity measured by means of the
visual water maze task was significantly decreased in the alpha7 KO mice and,
concordantly, there was a reduction of the cortical spatial resolution limit
measured by VEPs. However, the PERG was normal in alpha7 KO mice, compared to
control mice. The use of fluorescently tagged cholera toxin showed that
projections from the retina segregate normally in alpha7 KO mice and, in line
with this, the visual cortical responses elicited by stimulating either eye were
normally balanced in both visual cortices and showed no retinotopic
anomalies.Conclusions.Our findings indicate that the absence of the alpha7
nicotinic subunit reduces visual acuity. As the cortical output has an abnormal
spatial resolution but retinal output is preserved, we conclude that the low
visual acuity was due to a deficit specifically present in the visual cortex.

PMID: 22281823  [PubMed - as supplied by publisher]

21: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

The Posterior Location of the Dilator Muscle Induces Anterior Iris Bowing during
Dilation Even in the Absence of Pupillary Block.

Amini R, Whitcomb JE, Al-Qaisi MK, Akkin T, Jouzdani S, Dorairaj S, Prata T,
Illitchev E, Liebmann JM, Ritch R, Barocas VH.

Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN
55455.

Purpose:To examine the effect of the posterior location of the dilator on iris
anterior curvature during dilation.Methods:An in vivo human study, an ex vivo
porcine experiment, and an in silico computational model were performed in
parallel. Iris anterior curvature was measured in vivo before and after dilation
by time-domain slit lamp optical coherence tomography (SL-OCT). All patients (n
= 7) had previously had laser peripheral iridotomy to eliminate any pupillary
block due to primary angle-closure glaucoma. In the ex vivo experiments,
isolated porcine irides (n = 30) were secured at the periphery and immersed in
an oxygenated Krebs-Ringer buffer. Dilation was induced pharmaceutically by the
addition of 2.5% phenylephrine and 1% tropicamide. Iris images were taken before
and after dilation using an in-house optical coherence tomography (OCT) system.
A finite element model was also developed based on typical geometry of the iris
from the initial OCT image. The iris was modeled as a neo-Hookean solid, and the
active muscle component was applied only to the region specified as the
dilator.Results:An increase in curvature and a decrease in the chord length
after dilation were observed in both experiments. In both the in vivo and ex
vivo experiments, the curvature to chord length ratio increased significantly
during dilation. Computer simulations agreed well with the experimental results
only when the proper anatomical position of dilator was used.Conclusions:We
conclude that the posterior location of the dilator contributes to the anterior
iris bowing via a non-pupillary block dependent mechanism.

PMID: 22281822  [PubMed - as supplied by publisher]

22: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

Expression and Localization of Neural Cell Adhesion Molecule and PolySialic Acid
during Chick Corneal Development.

Mao X, Schwend T, Conrad GW.

Division of Biology, Kansas State University, Manhattan, KS.

Purpose:To assay for expression and localization of Neural Cell Adhesion
Molecule (NCAM) and Polysialic acid (polySia) in the chick cornea during
embryonic and postnatal development.Methods:Real time Q-PCR and Western blot
were used to determine NCAM expression and polysiaylation in embryonic,
hatchling and adult chick corneas. Immunofluorescence staining for NCAM and
polySia was conducted on cryosections of embryonic and adult corneas, whole
embryonic corneas and trigeminal neurons.Results:NCAM and ST8SiaII mRNA
transcripts peaked by E9, remained steady between E10 and E14 and slowly
decreased thereafter during embryonic development. Both gene transcripts showed
more than 190-fold decline in the adult chick cornea compared to E9. In
contrast, ST8SiaIV expression gradually decreased 26.5-fold from E6 to E19,
increased thereafter, and rose to the early embryonic level in the adult cornea.
Western blot analysis revealed NCAM was polysialylated and its expression
developmentally changed. Other polysiaylated proteins aside from NCAM were also
detected by Western blot analysis. Five NCAM isoforms including NCAM-120,
NCAM-180 and three soluble NCAM isoforms with low molecular weights (87-96kDa)
were present in chick corneas, with NCAM-120 being the predominate isoform. NCAM
was localized to the epithelium, stroma and stromal extracellular matrix (ECM)
of the embryonic cornea. In stroma, NCAM expression shifted from anterior to
posterior stroma during embryonic development and eventually became undetectable
in 20 wk adult cornea. Additionally, both NCAM and polySia were detected on
embryonic corneal and pericorneal nerves.Conclusions:NCAM and polySia are
expressed and developmentally regulated in chick corneas. Both
membrane-associated and soluble NCAM isoforms are expressed chick corneas. The
distributions of NCAM and polySia in cornea and on corneal nerves suggest their
potential functions in corneal innervation.

PMID: 22281821  [PubMed - as supplied by publisher]

23: Invest Ophthalmol Vis Sci. 2012 Jan 26; [Epub ahead of print] 

Vascular Endothelial Growth Factor-C Promotes Alloimmunity by Amplifying Antigen
Presenting Cell Maturation and Lymphangiogenesis.

Hajrasouliha AR, Funaki T, Sadrai Z, Hattori T, Chauhan SK, Dana R.

Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard
Medical School, Boston, Massachusetts.

Purpose:To investigate the role of anti-VEGF-C therapy in corneal graft survival
and concomitant suppression of hem- and lymph-angiogenesis.Methods:Corneal
suture model in BALB/C mice were placed and immunohistochemical staining was
performed with CD31/PECAM-1 and LYVE-1 to quantify the level of blood and
lymphatic vessels. Corneal transplants were done in BALB/c from C57BL/6 mice
donors; grafts were scored subsequently for opacity. VEGF-C was blocked in our
angiogenesis and transplant model using neutralizing monocolonal anti-VEGF-C
(VGX-100) by intra-peritoneal injection. To determine the function of VEGF-C in
maturation of antigen-presenting cells, we generated bone marrow-derived DC and
matured them in the presence or absence of VEGF-C.Results:We demonstrate that
VEGF-C expression is markedly up-regulated in corneal graft rejection. VEGF-C
blockade, through administration of a VEGF-C blocking monoclonal antibody,
suppresses corneal angiogenic responses, inhibits trafficking and maturation of
APCs, and significantly improves allotransplant survival.Conclusion:These data
suggest VEGF-C as a potentially important target in corneal transplant
pharmacotherapy and immunobiology.

PMID: 22281820  [PubMed - as supplied by publisher]

24: Invest Ophthalmol Vis Sci. 2012 Jan 24; [Epub ahead of print] 

The photopic negative response of the flash electroretinogram in multiple
sclerosis.

Wang J, Cheng H, Hu YS, Tang RA, Frishman LJ.

College of Optometry, University of Houston, Houston, TX.

Purpose.To evaluate retinal function in eyes of multiple sclerosis (MS) patients
with and without a history of optic neuritis (ON) using photopic
electroretinogram (ERG) and to compare functional and structural status of inner
retina.Methods.Full-field ERG responses to brief red flashes (0.04 to 2.8
cd-s/m(2)) on a rod-saturating blue background, were recorded from 51 MS
patients and 33 age-matched control subjects. In patients, Humphrey visual
fields (HVF) were measured, and peripapillary retinal nerve fiber layer
thickness (RNFLT) assessed, by optical coherence tomography (OCT) and GDx-VCC.
MS eyes were separated into ON>6 months (n=25), ON<6 months (n=29) and no-ON
(n=33) based on positive or negative history of ON, and time since last attack.
Thirteen ON<6 eyes were re-evaluated one year later.Results.PhNR amplitudes were
lower in ON>6, ON<6 and no-ON eyes (mean+/-SD, 17.3+/-7.6, 16.0+/-6.5,
23.8+/-9.3microV), than in control eyes (29.8+/-6.5microV, p<0.001) for a
standard stimulus of 1.42 cd-s/m(2); a- and b-wave amplitudes were unaffected.
PhNR amplitudes were correlated (p<0.05) with HVF Mean Deviation (MD) in ON>6
(r(2)=0.43) and no-ON eyes (r(2)=0.10), with similar results for weaker stimuli.
PhNR amplitudes were correlated with RNFLT in ON>6 eyes: OCT (r(2)=0.52,
p<0.0001); GDx (r(2)=0.51, p<0.01), and no-ON eyes: OCT (r(2)=0.21, p<0.01); GDx
(r(2)=0.17, p<0.05). ON<6 amplitudes were not significantly correlated with
other measures, but increased after one year by 5.1+/-3.1microV (p<0.001), HVF
MD by 1.8+/-2.3 dB (p<0.05), whereas RNFL loss persisted.Conclusion.Photopic ERG
PhNR amplitudes in MS patients are significantly reduced in eyes with and
without a history of ON.

PMID: 22273726  [PubMed - as supplied by publisher]

25: Invest Ophthalmol Vis Sci. 2012 Jan 24; [Epub ahead of print] 

Changes in corneal innervation and sensitivity and acetylcholine-mediated
vascular relaxation of the posterior ciliary artery in a type 2 diabetic rat.

Davidson EP, Coppey LJ, Holmes A, Yorek MA.

Department of Veterans Affairs Iowa City Health Care System and.

Purpose:Cornea confocal microscopy is emerging as a clinical tool to evaluate
the development and progression of diabetic neuropathy. The purpose of these
studies was to characterize the changes in corneal sensitivity and innervation
in a rat model of type 2 diabetes in relation to standard peripheral neuropathy
endpoints. Assessment of diabetes-induced changes in corneal innervation and
sensitivity in animal models will be important for determining the usefulness of
corneal markers for preclinical studies to test potential new treatments for
diabetic neuropathy.Methods:High fat/low dose streptozotocin diabetic rats were
used to examine diabetes-induced changes in standard diabetic neuropathy
endpoints and innervation of the cornea using confocal microscopy, corneal
sensitivity using a Cochet-Bonnet esthesiometer and vascular reactivity of the
posterior ciliary artery.Results:Compared to age-matched control rats induction
of hyperglycemia in high fat fed rats caused a decrease in nerve conduction
velocity, thermal hypoalgesia and a reduction in intraepidermal nerve fiber
profiles. In the cornea there was a decrease in corneal nerve fiber length and
sensitivity. In addition, vascular relaxation in response to acetylcholine was
decreased in the posterior ciliary artery.Conclusions:These studies suggest that
in a type 2 diabetic rat model changes in corneal nerve innervation and
sensitivity occur that are consistent with diabetic patients. Corneal
sensitivity and innervation may be valuable endpoints for examining the
potential treatments of diabetic neuropathy in preclinical studies.

PMID: 22273725  [PubMed - as supplied by publisher]

26: Invest Ophthalmol Vis Sci. 2012 Jan 24; [Epub ahead of print] 

AGE RELATED CHANGES IN VENOUS ENDOTHELIAL PHENOTYPE AT HUMAN RETINAL ARTERY-VEIN
CROSSING POINTS.

Yu PK, Tan PE, Morgan WH, Cringle SJ, McAllister IL, Yu DY.

Centre for Ophthalmology and Visual Science, The University of Western
Australia, Perth, Australia.

Purpose:To investigate the venous endothelial phenotype at retinal artery-vein
(AV) crossings and age-related changes in human cadaver eyesMethods:18 human
donor eyes free from known ocular pathologies were divided into two groups
depending on age (50 years). The central retinal artery was
cannulated and perfused with oxygenated Ringer's solution with 1% Bovine Serum
Albumin. The perfusate solutions were switched to fixative, membrane
permeablising solution, and selected labelling solutions for microfilament
f-actin and nucleic acid in vascular endothelial cells and smooth muscle cells.
The eyes were then immersion fixed and the retina flat-mounted. The venous
endothelial cells examined using confocal microscopic imaging techniques at the
AV crossing, pre AV crossing and post AV crossing regions.Results:There was no
significant difference in endothelial cell length upstream or downstream from an
AV crossing between the younger and older group. At the AV crossing, the venous
endothelia were shorter in the younger group and longer in the older group
compared to those upstream or downstream from the AV crossing. Stress fibres
were not frequently observed in the endothelial cells of younger donors.
However, the older group had numerous stress fibres in their endothelia at AV
crossing points.Conclusion:Age related phenotype changes in venous endothelial
cells have been identified in the region of AV crossings providing supportive
evidence for the hypothesis of age related and site-specific changes in the
vascular endothelial cells as an important factor contributing to the
pathogenesis of branch retinal vein occlusion.

PMID: 22273724  [PubMed - as supplied by publisher]

27: Invest Ophthalmol Vis Sci. 2012 Jan 24; [Epub ahead of print] 

Photoreceptor and Post-photoreceptoral Contributions to Photopic ERG a-wave in
Rhodopsin P347L Transgenic Rabbits.

Hirota R, Kondo M, Ueno S, Sakai T, Koyasu T, Terasaki H.

Department of Ophthalmology, Nagoya University Graduate School of Medicine,
Nagoya, Japan.

Purpose:The a-wave of the photopic electroretinogram (ERG) of macaque monkeys is
made up of the electrical activities of cone photoreceptors and
post-photoreceptoral neurons. However, it is not known whether the contributions
of these two components change in retinas with inherited photoreceptor
degeneration. The purpose of this study was to determine the contributions of
cones and post-photoreceptoral neurons to the a-wave of the photopic ERGs in
rhodopsin Pro347Leu transgenic (Tg) rabbits.Methods:Ten Tg and 10 wild-type (WT)
New Zealand White rabbits were studied at 4- and 12-months-of-age. The a-waves
of the photopic ERGs were elicited by xenon flashes of different stimulus
strengths before and after blocking the activities of post-photoreceptoral
neurons by intravitreal injections of a combination of 0.2-0.4 mM of
6-cyano-7-nitrouinoxaline-2,3(1H,4H)-dione, disodium (CNQX) and 2-4 mM of
(+/-)-2-amino-4-phosphonobutyric acid (APB).Results:The percentage contribution
of the cone photoreceptors to the photopic ERG a-waves increased with increasing
stimulus strength, and the percentage ranged from 54% to 75% in 4-months-old WT
rabbits. In contrast, the percentage contribution of the cone photoreceptors in
4-months-old Tg rabbits ranged from 32% to 51% (P<0.05). The mean percentage
contribution of cone photoreceptors became still smaller at 11% to 48% in
12-months-old Tg rabbits.Conclusions:These results suggest that the relative
contribution of cone photoreceptors to the photopic ERG a-wave is less in
retinas with inherited photoreceptor degeneration. This indicates that the
a-waves of the photopic ERGs in patients with retinitis pigmentosa must consider
this lower contribution from the cone photoreceptors.

PMID: 22273723  [PubMed - as supplied by publisher]

28: Invest Ophthalmol Vis Sci. 2012 Jan 24; [Epub ahead of print] 

Alterations in the Biomolecular Signatures of Developing Chick Corneas as
Determined by Biospectroscopy and Multivariate Analysis.

Pang W, Ahmadzai AA, Patel II, Qiu X, Liles M, Quantock AJ, Martin FL.

The School of Public Health, Guangxi Medical University, Nanning, Guangxi, PR
China;

Purpose.Biospectroscopy tools are increasingly being recognized as novel
approaches towards interrogating complex biological structures in a
non-destructive fashion. We set out in this study to apply these to investigate
alterations in the molecular signatures of developing chick corneas during the
onset and development of transparency.Methods.Embryonic chick corneas (n=46)
were obtained at two-day intervals from embryonic day 10 (E10) to day 18 (E18)
of incubation and interrogated using attenuated total reflection
Fourier-transform infrared (ATR-FTIR) spectroscopy and Raman microspectroscopy.
Resultant spectra were analyzed for variance using principal component analysis
and linear discriminant analysis (PCA-LDA).Results.Mean spectra following
ATR-FTIR spectroscopy or Raman microspectroscopy derived from corneas at each
developmental stage showed some overlap; however, in PCA-LDA scores plots a
clear segregation of spectra was evident and two-category discrimination
indicated that significant molecular alterations occur during tissue
morphogenesis. Notable by both techniques was the increasing intensity of DNA
signal (1080 cm(-1)) from E10 onwards, and major segregating biomarkers
identified by ATR-FTIR spectroscopy between E10 and E18 in the DNA/RNA (1126
cm(-1)), glycogen (1045 cm(-1)), protein (1470 cm(-1)), and Amide II (1512
cm(-1) and 1524 cm(-1)) spectral regions. Raman spectroscopy also identified
major distinguishing vibrational modes which included proteins, amino acids
(tyrosine, proline phenylalanine, valine), and secondary structures of proteins
(Amide I and Amide II).Conclusion.Developing chick cornea undergoes significant
changes in its biomolecular composition in the E10-E18 developmental period,
with the major changes in the spectral regions associated with DNA/RNA,
proteins, glycogen, and secondary protein structures.

PMID: 22273722  [PubMed - as supplied by publisher]

29: Invest Ophthalmol Vis Sci. 2012 Jan 24; [Epub ahead of print] 

Association of macular pigment density with plasma omega-3 fatty acids: the
PIMAVOSA Study.

Delyfer MN, Buaud B, Korobelnik JF, Rougier MB, Schalch W, Etheve S, Vaysse C,
Combe N, Le Goff M, Wolf-Schnurrbusch UE, Wolf S, Barberger-Gateau P, Delcourt
C.

: Univ. Bordeaux, Bordeaux, F-33000 France.

Purpose:To assess the correlation between macular pigment optical density and
plasma levels of lutein, zeaxanthin and fatty acids, especially omega-3
polyunsaturated fatty acids (PUFAs).Methods:The Pimavosa study is an
observational study which included 107 healthy volunteers aged 20 to 60 years,
born in the Southwest of France, without history of ocular disease. Macular
pigment optical density (MPOD) was measured using the two-wavelength
autofluorescence method with a modified scanning laser ophthalmoscope (HRA,
Heidelberg Engineering Inc, Heidelberg, Germany). Plasma measurements (lutein,
zeaxanthin and fatty acids) were performed from fasting blood samples collected
on the day of the eye examination.Results:MPOD within 6 degrees  correlated with
plasma levels of lutein and zeaxanthin (r=0.35, p<0.001 and r=0.30, p<0.005,
respectively). MPOD also significantly correlated with total plasma omega-3
PUFAs (r=0.22, p<0.05). Among the different omega-3 PUFAs, docosapentaenoic acid
(DPA) had the highest correlation with MPOD (r=0.31, p<0.001), while correlation
with eicosapentaenoic acid (EPA) was moderate (r=0.21, p<0.05), and did not
reach statistical significance for docosahexaenoic acid (DHA) (r=0.14,
p=0.14)Conclusions:In the present study, macular pigment density was associated
not only with plasma lutein and zeaxanthin, but also with omega-3 long-chain
PUFAs, and particularly with EPA and DPA. Further studies will be needed to
confirm these findings and identify the underlying mechanisms.

PMID: 22273721  [PubMed - as supplied by publisher]

30: Invest Ophthalmol Vis Sci. 2012 Jan 20; [Epub ahead of print] 

Analysis of progression of reticular pseudodrusen by spectral domain optical
coherence tomography.

Querques G, Poitrine FC, Coscas F, Massamba N, Querques L, Mimoun G, Bandello F,
Souied EH.

Department of Ophthalmology, Centre Hospitalier Intercommunal de Creteil
University Paris Est Creteil, Creteil, France.

Purpose:To analyze reticular pseudodrusen progression using
SD-OCT.Methods:Thirty-three consecutive patients (48 eyes) underwent Spectralis
SD-OCT using the eye-tracked follow-up protocol 24+/-2 months after baseline
examination. Each pair of B-scans (only 1 per eye was evaluated among those
showing pseudodrusen progression) was compared with respect to pseudodrusen
appearance and retinal layers structure. Stage 1 pseudodrusen was defined as
granular material between the RPE and the IS/OS, stage 2 as mounds of material
sufficient to alter the contour of the IS/OS, stage 3 as thicker material
adopting a conical appearance and breaking through the IS/OS, and stage 4 as
fading of the material due to reabsorption and migration within the inner
retinal layers.Results:A total of 78 pseudodrusen (detected on the 48 analyzed
B-scans, and counting for a mean of 2.3 pseudodrusen per scan) showed
progression over a mean of 23.9 +/- 1.2 months. All 58 pseudodrusen (100 %)
graded as stage 1 at baseline examination progressed to stage 2. Thirteen out of
16 pseudodrusen (81.3%) graded as stage 2 at baseline examination progressed to
stage 3, and 3 (18.7%) progressed to stage 4. All 4 pseudodrusen (100%) graded
as stage 3 at baseline examination progressed to stage 4.Among pseudodrusen
presenting stage 3 or 4 at follow-up (n=20), 100% had IS/OS disruption whereas,
12.1% (n=7) had IS/OS disruption among those at stage1 or 2 (n=58) (OR 1.736;
95% CI: 1.02- 2.43)Conclusions:The frequency of stage changes over time suggest
that reticular pseudodrusen are dynamic pathologic structures.

PMID: 22266524  [PubMed - as supplied by publisher]