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Biomedical subjects

M Rolando

Publications and source records attributed to M Rolando.

At least 19 recordsLinked to original sources
PubMed2005

The Lac repressor provides a reversible gene expression system in undifferentiated and differentiated embryonic stem cell.

Control of mammalian gene promoters by the bacterial LacI repressor provides reversible regulation and dose-response levels of derepressed expression by the lactose analog isopropyl thiogalactose (IPTG). Here, we show that insertion of LacI-binding sites in the ubiquitous beta-actin promoter confers a strong and dose-dependent IPTG-regulatable expression of transiently transfected reporter genes in mouse embryonic stem (ES) cells expressing LacI. We established ES cell lines stably expressing reporter genes under inducible control and found a five- to tenfold IPTG induction of transgene expression. The kinetics of induction is rapid and stable, and can be rapidly reversed after IPTG removal. Importantly, this regulatable expression was maintained throughout the differentiation process of ES cells, and observed in individual differentiated cardiomyocyte-like cells and neuronal-like cells. This reversible system is the first to function from undifferentiated to individual well-differentiated ES cells, providing a very useful tool to understand molecular mechanisms underlying ES cell self-renewal, commitment and differentiation.

Actins↗
PubMed2003

The Madrid triple classification of dry eye.

From the clinical point of view, there are many etiologic causes, several combinations of anatomo-pathologic manifestations, and different grades of severity of Dry Eye diseases in the dysfunctional tear film syndrome. The dacryologist doctor must recognize these three parameters, quantify them, and establish the most appropriate treatment. The present triple classification has been elaborated for this purpose. First, there is an etiologic distribution in ten groups: age-related, hormonal, pharmacologic, immunopathic, hyponutritional, dysgenetic, inflammatory, traumatic, neurodeprivative, and tantalic. Each of these groups comprise many variants. Second, there is an anatomo-pathologic classification named ALMEN classification from the acronym of aquodeficiency, lipodeficiency, mucodeficiency, epitheliopathy, and non-ocular exocrine affectations. Finally, there is a severity classification in five grades: subclinical (symptoms only when overexposure), mild (habitual symptoms), moderate (symptoms plus reversible signs), severe (symptoms plus permanent signs), and disabling (all the above, plus visual discapacity).

Dry Eye Syndromes↗
PubMed2001

Three-dimensional optic nerve head algorithm for the detection of glaucomatous damage.

PURPOSE: To determine whether a three-dimensional optic disc algorithm could be useful in differentiating optic nerve heads (ONH) with a normal visual field from those with an abnormal visual field also when using a simultaneous stereoscopic computerised ONH analyser. METHODS: One eye was randomly chosen from 45 normals and 55 patients with glaucoma (mean deviation -7.7 +/- 9.0 dB, corrected pattern standard deviation 3.1 +/- 2.3 dB). All the subjects were examined with the Humphrey Perimeter (program 30-2) and with the Topcon Image-net X Rev-3.51 b. Using the topographic map of the system, the algorithm of the third moment or cup shape measure was applied to the numbers (the number of points ranged from 623 to 1,883 depending on the size of the disc area) that identify the heights of all the points of the optic disc surface. Findings were analysed by means of the Mann-Whitney U test and receiver operator characteristic curves. RESULTS: The sensitivity and specificity of this three-dimensional ONH algorithm applied to Topcon Image-net was 90.6% and 85.1% respectively. No difference was found between the groups for age, disc area and number of the analysed points. CONCLUSIONS: The algorithm of cup shape measure or third moment is a useful parameter to separate eyes with normal from those with abnormal visual field also when using a simultaneous stereoscopic system such as Image-net.

Algorithms↗
PubMed2001

Quality of vision with presbyopic contact lens correction: subjective and light sensitivity rating.

PURPOSE: To quantify the quality of vision achieved with multifocal and bifocal contact lenses. METHODS: We analyzed differential light sensitivity by computerized automatic perimetry in 21 patients wearing monofocal soft contact lenses (group 1, controls) and multifocal and bifocal contact lenses (groups 2 and 3, respectively). Seven patients each were fitted with multifocal or bifocal contact lenses; seven patients were without contact lenses (without correction for testing the visual periphery and with near-vision correction using monofocal contact lens for testing the central 30 degrees of vision). The type of correction was randomly changed in a crossover fashion so that each eye was examined at different times with different corrections. Humphrey 640 VFA computerized automated perimetry was used to test visual fields at baseline, 45 days, and 3, 4.5, and 6 months. RESULTS: A statistically significant difference was found between the global sensitivities (GS) of the central visual field in patients with near-vision monofocal contact lenses and with bifocal contact lenses (P=0.0273) and between the GS of the central visual fields with multifocal contact lenses and with bifocal contact lenses (P=0.0261). In both cases, the GS were significantly reduced with bifocal contact lenses (total GS: group 1, 11256 dB (Decibels); group 2, 11154 dB; group 3, 10679 dB). CONCLUSIONS: The results indicate that there is reduced differential light sensitivity in the central 30 deg of the visual field with bifocal contact lenses compared with multifocal contact lenses and monofocal contact lenses (controls).

Contact Lenses, Hydrophilic↗
PubMed2001

The ocular surface and tear film and their dysfunction in dry eye disease.

The ocular surface, tear film, lacrimal glands, and eyelids act as a functional unit to preserve the quality of the refractive surface of the eye and to resist injury and protect the eye against changing bodily and environmental conditions. Events that disturb the homeostasis of this functional unit can result in a vicious cycle of ocular surface disease. The tear film is the most dynamic structure of the functional unit, and its production and turnover is essential to maintaining the health of the ocular surface. Classically, the tear film is reported to be composed of three layers: the mucin, aqueous, and lipid layers. The boundaries and real thickness of such layers is still under discussion. A dysfunction of any of these layers can result in dry eye disease.

Cornea↗
PubMed2001

Sjögren's syndrome as seen by an ophthalmologist.

Ocular surface involvement is a frequent feature of Sjögren syndrome characterized by the presence of typical symptoms such as burning and foreign body sensation and by wide spread epithelial damage of the cornea and on the conjunctiva. There is now evidence that local inflammatory changes and lacrymal gland-derived tear-borne pro-inflammatory agents have an important role in the build up and the maintenance, of ocular surface damage by the instauration of self maintaining vicious cycles. Inflammation causing decreased ocular surface sensation, resulting in further decreased tear secretion and decreased tear clearance, with growing concentration of pro inflammatory agents on the ocular surface. From the anatomic pathological point of view there is a not clarified discrepancy between the early highly depressed tear fluid production and the limited extension of involvement of the lacrymal gland. Proper gland stimulatory agents and control of inflammation could result in a better treatment than the palliative therapy available to day.

Disease Progression↗
PubMed2001

Ocular complications of latanoprost in uveitic glaucoma: three case reports.

The purpose of this study was to report paradoxical reaction on the intraocular pressure after treatment with latanoprost in 3 cases of uveitic glaucoma. Serial clinical examinations of intraocular pressure by means of daily tonometric curves were performed in three patients with uveitic glaucoma before and after the beginning of latanoprost therapy. All measurements were performed by two doctors, but every patient's IOP was always measured by the same doctor. Adverse reactions, such as increased intraocular pressure and recurrence of inflammation, were noted to occur 7 to 16 days after rechallenging with topical latanoprost therapy for glaucoma in patients with history of uveitic glaucoma. The conclusion indicates that clinicians should be alerted to these possible complications of topical latanoprost therapy in uveitic glaucoma.

Antihypertensive Agents↗
PubMed2001

Daily tonometric curves after cataract surgery.

AIM: To evaluate daily tonometric curves after cataract surgery in patients with cataract only and in patients with cataract and glaucoma. METHODS: 108 patients scheduled for cataract surgery were randomly allocated to two groups: 57 patients with cataract only (normal) and 51 with cataract and primary open angle glaucoma (POAG). All patients underwent extracapsular cataract extraction (ECCE) (manual technique with long wound), phacoemulsification (automated technique with short wound), or nucleus capture (manual technique with short wound). Intraocular pressure (IOP) was measured by Goldmann tonometry in all patients every 2 hours for 12 hours before the operation and at 1 and 6 months postoperatively. RESULTS: 79 patients completed the 6 month examination. ECCE resulted in greater reductions in IOP than the other procedures (ECCE: 27% and 36% in normal patients and those with POAG, respectively; nucleus capture: 20% and 31%, respectively; phacoemulsification: 19% and 22%, respectively). The fluctuations in IOP before and after surgery were not statistically significant. CONCLUSION: Cataract surgery in normal patients reduces IOP but does not eliminate fluctuations which are directly proportional to the IOP value and result partly from circadian rhythms. This important finding might influence our approach to treatment of patients with glaucoma.

Aged↗
PubMed2000

A standardized visual scale for evaluation of tear fluorescein clearance.

OBJECTIVE: To evaluate the correlation and the agreement between a validated fluorometric technique (fluorescein clearance test) and a newly developed, clinically practical standardized visual scale to evaluate tear fluorescein clearance. Also, the ability of this new method to distinguish healthy persons from patients reporting ocular irritation associated with meibomian gland disease (MGD), aqueous tear deficiency (ATD), or both was tested. DESIGN: Case-controlled study. PARTICIPANTS: Healthy persons (n = 32), patients with MGD associated with rosacea (n = 30), patients with noninflammatory atrophic MGD (n = 24), and patients with ATD (n = 39) were evaluated. There was a similar age and gender distribution in each group. METHODS: Each subject completed a symptom questionnaire and had the following tests performed: fluorescein clearance test (FCT), standardized visual scale test (SVST), corneal fluorescein staining, Schirmer 1 test, corneal and conjunctiva sensitivity, and eyelid margin and meibomian gland examination. MAIN OUTCOME MEASURES: The FCT was performed with a CytoFluor II fluorophotometer by measuring the fluorescein concentration in minimally stimulated tear samples collected from the inferior tear meniscus 15 minutes after instillation of 5 microl of 2% sodium fluorescein. The SVST score, ranging from 0 to 6, was obtained by comparing the colors of the standardized visual scale with the color of the lateral inferior tear meniscus immediately before tear collection for the FCT. Severity of ocular irritation was assessed with a symptom questionnaire. Schirmer 1 test (without anesthesia), biomicroscopic meibomian gland evaluation, and corneal fluorescein staining were performed. Corneal and conjunctival sensitivity scores were assessed with the Cochet-Bonnet aesthesiometer. The correlation and the agreement between FCT, FCT corrected for Schirmer test (corrected FCT), SVST, and SVST corrected for Schirmer test (corrected SVST) in separating healthy persons from patients with ATD, MGD, or both were studied. Furthermore, the correlations of FCT, corrected FCT, SVST and corrected SVST, corneal fluorescein staining score, corneal and conjunctiva sensitivity, meibomian gland and eyelid evaluation, and questionnaire score were studied. RESULTS: The FCT, the corrected FCT, the SVST, and the corrected SVST all showed strong correlation with irritation symptoms, corneal fluorescein staining, Schirmer 1 test score, cornea and conjunctiva sensitivity, and meibomian gland and eyelid pathologic characteristics. The FCT, the corrected FCT, the SVST, and the corrected SVST had a sensitivity in diagnosing MGD, respectively, of 67%, 72%, 69%, and 76%, and of 95%, 97%, 97%, and 97% in diagnosing ATD. The specificity was, respectively, 97%, 96%, 97%, and 94%. CONCLUSIONS: The new standardized visual scale test was equivalent to fluorometric assessment of tear clearance in its correlation with irritation symptoms, ocular surface and eyelid disease, and ocular surface sensitivity. Its ability to separate healthy persons from patients with MGD and ATD was improved by applying a correction factor based on Schirmer test score. The new standardized visual scale test is an accurate and practical method for clinical assessment of fluorescein tear clearance.

Case-Control Studies↗
PubMed2000

Echographic study of extraocular muscle thickness in children and adults.

BACKGROUND: Echobiometric evaluation of extraocular muscles in normal subjects has been performed previously, but only in adults. We determined extraocular muscle thickness in normal subjects in three age groups. METHODS: Extraocular muscle thickness was studied in 75 normal subjects divided into three age groups (5-10, 11-15 and 28-37 years) using a Biovision B-scan-S instrument in standardized A-mode (frequency, 10 MHz; biometry resolution, 0.15 mm; depth, 40-60 mm; points on X axis, 512; levels on Y axis, 256). All measurements were performed by the same operator and repeated five times. The reproducibility of the technique was determined using the coefficient of variation. The one-way ANOVA test was used to compare the three groups, and the two-tailed unpaired t-test was used to compare subjects aged 5-10 years and those aged 11-15 years, and subjects aged 11-15 years with those aged 28-37 years. RESULTS: The technique showed good reproducibility. In subjects 5-10 years old, the coefficient of variation was 8%; in subjects 11-15 years and 28-37 years old, it was 5%. Increased muscle thickness was observed with age (p < 0.001). A statistically significant difference between the medial and inferior recti muscles in subjects 11-15 years and 28-37 years old was found (p < 0.001). CONCLUSIONS: The increased thickness of all recti muscles may be influenced by growth (primarily during puberty), and the variations in thickness of the extraocular muscles may be attributable to near-vision stimulus of the inferior and medial recti muscles.

Adolescent↗
PubMed2000

Improvement of the ocular surface using hypotonic 0.4% hyaluronic acid drops in keratoconjunctivitis sicca.

BACKGROUND: The ocular surface changes of keratoconjunctivitis sicca (KCS) could be the result of the effect of an altered tear film on the epithelial environment. PURPOSE: To evaluate the possibility of improving the environmental conditions of the ocular surface by lowering tear osmolarity, increasing tear film volume and stabilising the tear film. Also, to study the effect of such an improvement on the epithelial cells of the ocular surface. METHODS: One hundred and thirty-five patients with a diagnosis of KCS were treated on a randomised basis with either unpreserved hypotonic 0.4% hyaluronic acid (HHA) eye drops or 0.3% hydroxypropylmethylcellulose plus 0.1% Dextran 70 (HPMC) eye drops 6 times a day for 60 or 90 days. In all patients a Schirmer I test, break-up time (BUT), ocular surface staining with 1% Bengal Rose, or 2% fluorescein, as well as subjective symptoms, were recorded before and 15, 30 and 60 days after the beginning of the study. Patients were divided into three subgroups and the effect of the treatment was studied using three different techniques: the tear ferning test, conjunctival impression cytology and tear osmolarity measurement. RESULTS: Improvements in BUT, vital staining, Schirmer I and symptoms were recorded in both groups of treatment, with significant differences for patients treated with 0.4% HHA. On day 60, 30 min after installation: tear ferning patterns changed from 100% pathological (types III-IV) to 93% physiological (types I-II) in the 0.4% HHA group and from 100% pathological to 78% physiological in the 0.3% HPMC group (p < 0.01 between groups). Tear osmolarity shifted from 353 +/- 23 to 305 +/- 6 mosmol/l in the 0.4% HHA group and from 346 +/- 15 to 336 +/- 8 mosmol/l in the 0.3% HPMC group (p < 0.001 between groups). On day 90, the impression cytology score improved from 1.2 to 1.9 in the 0.4% HHA group while it did not change in the 0.3% HPMC group (p < 0.05 between groups). CONCLUSION: In KCS appropriate treatment with a hypotonic 0.4% HHA tear substitute can change the tear environment and results in improvement of the epithelial conditions of the ocular surface.

Adjuvants, Immunologic↗
PubMed1999

Optic disc surface smoothness and visual field indices.

BACKGROUND: In order to ascertain whether the optic disc surface smoothness (ODSS) could be used to predict the amount of visual field damage in glaucomatous eyes, the correlations between ODSS and visual field indices were evaluated. METHODS: One eye was randomly chosen from each of 40 normals and 50 patients with glaucoma. The morphology of the optic disc surface was analyzed using the Topcon IMAGEnet X Rev-3.51b. In order to define the level of "smoothness" of the optic disc surface, the differences of the relative position of each surface point was studied by measuring the standard deviation (SD) from the average height of the points (number of points ranged from 623 to 1883 depending on the size of the disc area) that identify the optic disc surface. All the subjects were also examined with the Humphrey perimeter (Program 30-2) and the results were analyzed by Mann-Whitney U-test and Spearman rank correlation coefficient. RESULTS: The difference in ODSS between the glaucomatous and the normal eyes was statistically significant. No significant correlation was found between age and ODSS. A significant correlation was found between ODSS and mean deviation (MD) and between ODSS and corrected pattern standard deviation (CPSD). In the glaucoma group there were significant correlations between ODSS and the perimetric indices MD and CPSD; no correlations were found in the normal group. CONCLUSION: The ability of ODSS to reflect the level of visual field change in glaucomatous eyes appears to be rather limited, even if statistically significant. This fact does not limit the clinical usefulness of ODSS as a diagnostic parameter in consequence of its strong correlations with the other morphometric parameters and its high sensitivity and specificity in separating normal from glaucomatous eyes.

Female↗
PubMed1999

Small incision nucleus capture: results of 200 cases.

PURPOSE: To compare the learning curve in a series of 200 cataract surgeries performed using small incision nucleus capture with that of phacoemulsification as reported in the literature. SETTING: Department of Ophthalmology, University of Genoa, Genoa, Italy. METHODS: Two hundred eyes of 163 consecutive patients with cataract had small incision nucleus capture, a relatively new cataract surgery technique that allows small incisions and in-the-bag intraocular lens implantation. Patients were divided into 4 groups of 50 each according to when they had surgery between August 1996 and October 1997. The incidence of intraoperative complications (capsule break with or without vitreous loss, capsulorhexis tears, Descemet's detachment, transient iris damage) and postoperative complications (raised intraocular pressure, corneal epithelial edema, Descemet's folds, and permanent iris damage) were evaluated at the different time points. Also recorded was final visual acuity. These results were compared with those obtained with phacoemulsification. RESULTS: The study comprised 92 women and 71 men with an age range of 41 to 93 years. Overall final results showed that the learning curve of nucleus capture is comparable to that of phacoemulsification. CONCLUSION: Nucleus capture cataract extraction resulted in a low incidence of complications and good visual recovery that was comparable to that obtained with phacoemulsification.

Adult↗
PubMed1999

Evaluation of the analgesic effect of 0.1% indomethacin solution on corneal abrasions.

PURPOSE: The authors wished to verify the analgesic action of 0.1% indomethacin in a water-based solution on patients affected by traumatic corneal abrasions. METHODS: 347 patients affected by traumatic corneal abrasions, having been randomly divided into 2 groups on the basis of the administration of indomethacin, were evaluated at 30 min, 12 h and 24 h after the initial treatment of the abrasion. The level of pain experienced was evaluated on a verbal pain scale and the healing time was evaluated relative to the dimension of the abrasion. RESULTS: The pain level was initially overwhelming for both groups: p = 0.737; at successive check-ups it was possible to verify a reduction of the symptomatology, with a more pronounced decrease in pain in the group treated with indomethacin (p < 0.0001), which also demonstrated a lower sensitivity to pain in the case of larger lesions (p < 0.0001). There was no difference in the healing time between groups, and the reduction of pain is not correlated with corneal anesthesia and healing time. CONCLUSIONS: Our study highlighted the efficacy of indomethacin as a pain reducer for acute corneal pathology and suggested that the medication may act on the corneal nociceptors in a qualitative way.

Adult↗