13 research outputs found
Conjunctival Short-term Evolution after Pterygium Excision
Purpose To analyze conjunctival cytological features 1 month after pterygium excision using limbo-conjunctival autograft (LCA) with and without intraoperative mitomycin C and to assess tissue short-term evolution in both situations.; Methods Fifty-nine primary nasal pterygia from 59 patients were excised with LCA. Twenty-nine were treated with intraoperative mitomycin C 0.02% (MMC+) and 30 were treated without it (MMC-). Impression cytology was performed in nasal and temporal conjunctiva before and 1 month after the excision. Goblet cell density (GCD) and nucleus-to-cytoplasm nongoblet epithelial cell ratio were quantified.; Results Surgical strategy comparisons (intergroup comparisons): All the preoperative data were, in mean, within the reference range, except for a slight goblet cell hyperplasia in the area of the lesion in MMC+ but no significant differences were found between the groups (p = 0.079 for GCD and p = 0.245 for nucleus-to-cytoplasm ratio; analysis of variance). Clinically relevant differences after surgery were only shown in nasal GCD that was significantly lower in MMC+ than in MMC- (p = 0.000; analysis of variance), with the mean value in MMC+ slightly below normal values whereas that in MMC- remained normal. Tissue evolution (intragroup comparisons): No clinically relevant changes were found in MMC-. Data from MMC+ displayed no changes 1 month after surgery, except for nasal GCD that showed a significant reduction (p = 0.000; paired t test). Nevertheless, this GCD decrease was more modest than that previously described using mitomycin C without autograft, because in the present study, nasal GCD was not lower but similar to postoperative temporal data of the same eye (p = 0.164; paired t test).; Conclusions Limbo-conjunctival autograft is a good technique for conjunctiva early recovery. When mitomycin C was added, the GCD reduction was lower than described using other surgical techniques. Mitomycin C, in optimal concentration and exposure, associated with LCA could be a good clinical option to minimize pterygium recurrence.Postprint (author's final draft
Estudi morfològic i biomètric de diferents espècies d'insectÃvors i rosegadors
[cat] S'estudien diferents aspectes relacionats amb les caracterÃstiques anatòmiques, histològiques, ultraestructurals i morfomètriques de les estructures que formen l'òrgan de la visió de sis espècies d'insectÃvors ( Sorex minutus, S. araneus, S. coronatus, Neomys fodiens, Crocidura russula i Talpa europaea) i de deu espècies de rosegadors ( Clethrionomys glareolus, Arvicola terrestris, Chionomys nivalis, Microtus gerbei, M. duodecimcostatus, M. arvalis, Apodemus sylvaticus, Mus domesticus, M. Spretus i Eliomys quercinus) capturats en els seus hà bitats naturals. Els objectius concrets de la memòria consisteixen en relacionar les diferències i similituds interespecÃfiques de l'òrgan de la visió amb els hà bitats i els patrons d'activitat temporal de cada espècie, tant des del punt de vista funcional com filogenètic. En definitiva, es realitza un estudi sobre l'ecologia de la visió de les espècies considerades. Excepte a T. Europaea, a on apareixen estructures oculars en estat regressiu com a resposta a la seva activitat hipogea, els ulls de les espècies d'insectÃvors analitzades, estan ben desenvolupats, tot i les seves reduïdes dimensions. La còrnia està coberta per una capa multilaminar formada per cèl·lules mortes que podria augmentar l'Ãndex de refracció de la còrnia i, per tant, el poder diòptric de l'ull. A més, presenten caracterÃstiques que afavoreixen la visió diürna, com una distà ncia nodal posterior del globus ocular proporcionalment gran, un cristal·là voluminós però amb la cara posterior més aplanada que l'anterior, i un percentatge de cons que, en general, supera el 5% del total de cèl·lules fotoreceptores, particularment en els representants del gènere Sorex. En les espècies d'aquest mateix gènere s'ha detectat la presència de mitocondris gegants (megamitocondris) als el·lipsoides dels cons. En mamÃfers, aquests orgà nuls només han estat descrits prèviament als cons de les retines del gènere Tupaia (Scandentia) i, probablement incrementen l'eficà cia òptica d'aquests fotoreceptors. L'ull de N. Fodiens mostra adaptacions oculars pròpies dels animals semiaquà tics, i li permeten veure-hi tant a dins com a fora de l'aigua. En el cas dels rosegadors, les espècies d'arvicolins estudiades mostren millors adaptacions a una visió crepuscular o diürna que els ulls dels murins considerats, particularment M. Arvalis. AixÃ, la densitat de bastonets és inferior a la dels murins pel que la seva sensibilitat a la llum serà també inferior. Per contra, la proporció més elevada de cons els dotarà d'una major agudesa visual. A més, els ulls són proporcionalment més petits degut a la seva activitat cavadora. Els globus oculars d' A. Terrestris conserven caracterÃstiques oculars, tant anatòmiques com morfomètriques que indicarien un primer origen semiaquà tic i diürn, seguides per una readaptació a les condicions de baixa il·luminació de l'interior de les galeries. En canvi, els murins mostren caracterÃstiques oculars eminentment nocturnes, no només per la seva mida, els ulls d' A. Sylvaticus són tan grans que li sobresurten del cap, sinó també per la forma dels seus dioptris i l'estructura histològica de totes les túniques oculars, especialment de la retina. Els resultats obtinguts corroboren la relació entre la morfologia i la biometria de les estructures oculars amb els hà bits i els hà bitats de les espècies considerades. S'estableix que malgrat les reduïdes dimensions oculars, les modificacions en la mida i forma de l'ull i dels seus dioptris (còrnia i cristal·lÃ) permeten aconseguir una visió adequada per tal que les espècies estudiades puguin adaptar-se a diferents condicions de llum ambiental. També es constata que les espècies filogenèticament emparentades comparteixen un mateix model d'ull i que és aquest model el que ha anat variant, tant des del punt de vista biològic com òptic, per permetre una millor adaptació de les espècies a nous hà bitats
Genetic and molecular analysis of the recR locus of Escherichia coli K-12
SIGLEAvailable from British Library Document Supply Centre- DSC:D172172 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Whats biomarkers explain about pterygium OCT pattern
Background Optical coherence tomography (OCT) has become
a very useful tool to study in vivo different ocular structures
and to improve differential diagnosis and management of
many ocular pathologies. This study aims to identify pterygium
alterations that trigger characteristic OCT images, and
analyze if this pattern correctly demarcates lesion boundary.
Methods Thirty-two patients, 22 men, and ten women, aged
between 26 and 56 (mean age 40.5±6.9) with symptomatic
primary pterygium were recruited. After excision, lesion images
were obtained by high-definition OCT. Specimens were
stained with hematoxylin–eosin (H&E), antivimentin for all
mesenchymal origin cells and altered limbal basal cells, CD45
for lymphocyte and macrophage cells, CD1a for Langerhans
cells, and S100 for melanocyte and Langerhans cells.
Results The typical OCT wedge-shape hyperreflective mass
was evident only by vimentin antibody and included, mainly,
fibroblasts but also immune cells (verified by CD45) in a rich
network of collagen fibers. The mass apex, often extended
centripetally as a thin subepithelial line, hyperreflective by
OCT, was formed by a row of fibroblasts under an apparently
intact Bowman’s layer, as vimentin samples revealed.
Hyperreflective epithelium overlying the mass showed a great
number of vimentin-positive infiltrated cells such as melanocytes,
Langerhans cells, and lymphocytes (identified by the
other biomarkers). H&E staining revealed the presence of
goblet cells. Nevertheless, only vimentin staining revealed
the presence of altered basal cells above partially dissolved
or apparently intact Bowman’s layer, coinciding in this last
case with the fibroblast subepithelial line. In most of the cases
(72 %), the altered cells occupied a basal segment shorter than
the fibroblast subepithelial line but in some specimens, these
cells exceeded the fibroblast line length.
Conclusions This study demonstrated the great visual accordance
between pterygium OCT images and vimentin staining.
Alteration in collagen arrangement, infiltration of inflammatory
cells, and fibroblast subepithelial line in the lesion apex
were the main histological changes responsible for the anomalous
hyperreflectivity of the OCT pattern. By contrast, altered
basal cells located in the basal epithelial layer of the
pterygium head could not be detected by OCT, which might
generate lesion size underestimation
Tear osmolarity and ocular changes in pterygium
Purpose: To determine abnormalities in tear osmolarity (TO), tear function, and impression cytology in patients with pterygium and to assess the relationship between the variables. Methods: Thirty eyes from 30 patients with primary nasal pterygium and 30 eyes from 30 volunteers without ocular pathologies or dry eye symptoms were enrolled in the present study. TO test, tear ferning test, fluorescein tear breakup time, Schirmer test, and impression cytology of the conjunctiva were performed. Analysis of variance was applied for intergroup comparisons, and Pearson correlation was used to calculate the strength of relationships between the variables. A statistical significance level of P<0.05 was considered. Results: Pterygium patients had significantly higher TO, lower crystallization percentage, and lower goblet cell density (GCD) than control patients. A weak but significant negative correlation seems to exist between TO and crystallization percentage (r=-0.425, P<0.01) and between TO and GCD (r=-0.295, P<0.05). Conclusion: There is evidence to suggest that pterygium appears to induce unfavorable conditions of increasing TO that could trigger alterations in tear crystallization and GCD. Being aware of TO changes seems essential to understand the complex relationship among pterygium, tear film functions, and ocular surface changes.Peer ReviewedPostprint (published version
Item by item analysis strategy of the relationship between symptoms and signs in early dry eye
Postprint (published version
Item by item analysis strategy of the relationship between symptoms and signs in early dry eye
Conjunctival Short-term Evolution after Pterygium Excision
Purpose To analyze conjunctival cytological features 1 month after pterygium excision using limbo-conjunctival autograft (LCA) with and without intraoperative mitomycin C and to assess tissue short-term evolution in both situations.; Methods Fifty-nine primary nasal pterygia from 59 patients were excised with LCA. Twenty-nine were treated with intraoperative mitomycin C 0.02% (MMC+) and 30 were treated without it (MMC-). Impression cytology was performed in nasal and temporal conjunctiva before and 1 month after the excision. Goblet cell density (GCD) and nucleus-to-cytoplasm nongoblet epithelial cell ratio were quantified.; Results Surgical strategy comparisons (intergroup comparisons): All the preoperative data were, in mean, within the reference range, except for a slight goblet cell hyperplasia in the area of the lesion in MMC+ but no significant differences were found between the groups (p = 0.079 for GCD and p = 0.245 for nucleus-to-cytoplasm ratio; analysis of variance). Clinically relevant differences after surgery were only shown in nasal GCD that was significantly lower in MMC+ than in MMC- (p = 0.000; analysis of variance), with the mean value in MMC+ slightly below normal values whereas that in MMC- remained normal. Tissue evolution (intragroup comparisons): No clinically relevant changes were found in MMC-. Data from MMC+ displayed no changes 1 month after surgery, except for nasal GCD that showed a significant reduction (p = 0.000; paired t test). Nevertheless, this GCD decrease was more modest than that previously described using mitomycin C without autograft, because in the present study, nasal GCD was not lower but similar to postoperative temporal data of the same eye (p = 0.164; paired t test).; Conclusions Limbo-conjunctival autograft is a good technique for conjunctiva early recovery. When mitomycin C was added, the GCD reduction was lower than described using other surgical techniques. Mitomycin C, in optimal concentration and exposure, associated with LCA could be a good clinical option to minimize pterygium recurrence
Topographic corneal changes in astigmatism due to pterygium´s limbal-conjuctival autograft surgery
Postprint (published version