Serological Survey for Antibodies to Encephalitozoon cuniculi in Ownerless Dogs From Urban Areas of Brazil and Colombia

There are 3 strains of Encephalitozoon cuniculi that occur in mammals. Strain III is associated with clinical disease in dogs, although some can be asymptomatic carriers and excrete spores in their urine. Several cases of human E. cuniculi infection caused by strain III have been observed in immunocompromised patients, indicating that E. cuniculi should be considered a zoonotic agent. Encephalitozoon cuniculi can cause fatal disease in maternally-infected or young dogs. Clinical signs in these animals included blindness, encephalitis, retarded growth rate, and nephritis. Encephalitozoon cuniculi has also been associated with primary renal failure in adult dogs. The present study used the direct agglutination test (DAT, cut-off 1:50) and the indirect fluorescent antibody test (IFAT, cut-off 1:10) to examine the prevalence of antibodies to E. cuniculi in dogs from Brazil and Colombia. Using the DAG, 31 (27.4%) of 113 dogs from Brazil and 47 (18.5%) of 254 dogs from Colombia were seropositive. Nine (14.3%) of 63 dogs from Brazil and IS (35.3%) of the 51 dogs from Colombia were seropositive by indirect immunofluorescent antibody test. These results indicate that dogs from Brazil and Colombia are exposed to E. cuniculi.

Theoretical study on the molecular and electronic properties of some substances used for diabetes mellitus treatment

Diabetes mellitus (DM) is a disease that affects a large number of people, and the number of problems associated with the disease has been increasing in the past few decades. These problems include cardiovascular disorders, blindness and the eventual need to amputate limbs. Therefore, the quality of life for people living with DM is less than it is for healthy people. In several cases, metabolic syndrome (MS), which can be considered a disturbance of the lipid metabolism, is associated with DM. In this work, two drugs used to treat DM, pioglitazone and rosiglitazone, were studied using theoretical methods, and their molecular properties were related to the biological activity of these drugs. From the results, it was possible to correlate the properties of each substance-particularly electronic properties-with the biological interactions that are linked to their pharmacological effects. These results suggest that there are future prospects for designing or developing new drugs based on the correlation between theoretical and experimental properties.

Vibration-enhanced posture stabilization achieved by tactile supplementation: May blind individuals get extra benefits?

Diminished balance ability poses a serious health risk due to the increased likelihood of falling, and impaired postural stability is significantly associated with blindness and poor vision. Noise stimulation (by improving the detection of sub-threshold somatosensory information) and tactile supplementation (i.e. additional haptic information provided by an external contact surface) have been shown to improve the performance of the postural control system. Moreover, vibratory noise added to the source of tactile supplementation (e.g. applied to a surface that the fingertip touches) has been shown to enhance balance stability more effectively than tactile supplementation alone. In view of the above findings, in addition to the well established consensus that blind subjects show superior abilities in the use of tactile information, we hypothesized that blind subjects may take extra benefits from the vibratory noise added to the tactile supplementation and hence show greater improvements in postural stability than those observed for sighted subjects. If confirmed, this hypothesis may lay the foundation for the development of noise-based assistive devices (e.g. canes, walking sticks) for improving somatosensation and hence prevent falls in blind individuals. (C) 2011 Elsevier Ltd. All rights reserved.

What's scene and not seen: Influences of movement and task upon what we see

Studies concerning the processing of natural scenes using eye movement equipment have revealed that observers retain surprisingly little information from one fixation to the next. Other studies, in which fixation remained constant while elements within the scene were changed, have shown that, even without refixation, objects within a scene are surprisingly poorly represented. Although this effect has been studied in some detail in static scenes, there has been relatively little work on scenes as we would normally experience them, namely dynamic and ever changing. This paper describes a comparable form of change blindness in dynamic scenes, in which detection is performed in the presence of simulated observer motion. The study also describes how change blindness is affected by the manner in which the observer interacts with the environment, by comparing detection performance of an observer as the passenger or driver of a car. The experiments show that observer motion reduces the detection of orientation and location changes, and that the task of driving causes a concentration of object analysis on or near the line of motion, relative to passive viewing of the same scene.

Management of canine diabetes

The majority of diabetic dogs appear to have a form of type 1 diabetes analogous to the latent autoimmune diabetes of adults (LADA) in humans. Evidence of acute or chronic pancreatitis occurs in about 40% of diabetic dogs. Blindness caused by cataract formation eventually occurs in the majority of diabetic dogs and is not dependent on glycemic control. Insulin is the mainstay of therapy for diabetic dogs, and a conservative approach to insulin therapy is crucial. Most diabetic dogs require twice-daily dosing with lente or NPH insulin to adequately control their clinical signs. The diet fed should primarily be palatable and nutritionally balanced. Improved glycemic control may be achieved in some dogs if the diet contains increased insoluble fiber.

Interability interactions: Impact of type and visibility of disability on perceptions

Research on perceptions of people with disabilities has in general focussed on a single disability or on unspecified 'disability.' The aim of this study was to compare perceptions of several acquired disabilities from an intergroup perspective. It was hypothesised that the type (sensory or motor) and visibility of the disability would influence perceptions, and that prior contact would increase the positivity of perceptions. Participants were 155 students who gave their own, other, perceived self, and communication perceptions of male and female targets (with deafness, blindness, aphasia, or paraplegia) in vignettes. Results indicated that for most measures, people with motor disabilities were perceived more negatively than those with sensory ones, visible sensory disabilities more negatively than invisible sensory, but contrary to predictions, invisible motor more negatively than visible motor. There was some support for the association between prior contact and more positive perceptions.

Differences in the early biomechanical effects of hyperopic and myopic laser in situ keratomileusis

PURPOSE: To compare changes in corneal hysteresis (CH) and the corneal resistance factor (CRF) in myopic and hyperopic laser in situ keratomileusis (LASIK) and evaluate their relationship to the number of photoablative pulses delivered, a surrogate for ablation volume. SETTING: Cleveland Clinic Cole Eye Institute, Cleveland, Ohio, USA. METHODS: Preoperative and 1-week postoperative Ocular Response Analyzer measurements in eyes that had femtosecond-assisted LASIK were studied retrospectively. Changes in CH and CRF were compared and tested for correlation with the number of excimer laser pulses. RESULTS: Thirteen myopic eyes and 11 hyperopic eyes were evaluated. Preoperative corneal thickness, CH, CRF, programmed correction magnitude, flap thickness, and total number of fixed spotsize photoablative pulses were similar in the 2 groups (P>.1). Decreases in CH and CRF were greater after myopic LASIK than after hyperopic LASIK (P<.005), and changes in CRF were correlated with the number of excimer laser pulses in the myopic group only (r = -0.63, P = .02). Regardless of ablation profile, changes in CH were more strongly correlated with preoperative CH values than with attempted ablation volume. CONCLUSIONS: With comparable flap thickness and attempted ablation volumes, myopic photoablation profiles were associated with greater decreases in CRF and CH than hyperopic profiles. Results indicate that preoperative corneal biomechanical status, ablation volume, and the spatial distribution of ablation are important factors that affect corneal resistance and viscous dissipative properties differently. Preferential tissue removal in the natively thicker paracentral cornea in hyperopia may partially account for the rarity of ectasia after hyperopic LASIK.

Early keratocyte apoptosis after epithelial scrape injury in the human cornea

Animal studies in mice, rats, rabbits, pigs and hens demonstrated that anterior keratocytes undergo programmed cell death or apoptosis after corneal epithelial injury. Many other wound healing changes subsequently follow the keratocyte apoptosis response. This study evaluated early keratocyte apoptosis after corneal epithelial scrape injury in human eyes scheduled for enucleation for malignancy. Two eyes had corneal epithelial scrape 1 h prior to the enucleation and another eye served as a control and had no corneal scrape prior to enucleation. One additional eye was enucleated, washed with balanced salt solution, and then had the corneal epithelium scraped 1 h prior to processing for analysis. Apoptosis was identified by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and confirmed by transmission electron microscopy (TEM). Anterior keratocyte apoptosis was detected in the three corneas that had epithelial scrape injury, but not in the control unwounded cornea. This study confirmed that keratocyte apoptosis is also an early response to corneal epithelial injury in humans and showed that tears are not essential for keratocyte apoptosis to occur in response to epithelial injury. (C) 2009 Elsevier Ltd. All rights reserved.

Stromal interleukin-1 expression in the cornea after haze-associated injury

The purpose of this study was to determine whether myofibroblasts or other cells in the stroma in the cornea produce interleukin (IL)-1 alpha or IL-1 beta that could modulate myofibroblast viability in corneas with haze after photorefractive keratectomy (PRK). Twenty-four female rabbits had haze-generating PRK for 9 diopters of myopia and were sacrificed at 1 week, 2 weeks, 3 weeks or 4 weeks after surgery. Corneal rims were removed, frozen in OCT at -80 degrees C, and analyzed by immunocytochemistry using primary antibodies to IL-1 alpha, IL-1 beta and alpha smooth muscle actin (SMA). Double immunostaining was performed for the co-localization of SMA with IL-1 alpha or IL-1 beta. Central dense haze and peripheral slight haze regions of each cornea were analyzed. SMA+ cells that expressed IL-1 alpha protein were detected in both regions of the corneas at most time points following PRK. However, in the haze region at the 1,3 and 4 week time points, significantly more (p < 0.01) SMA cells did not express IL-1 alpha. Also, in the haze region at all three time points, significantly more (p < 0.01) SMA- cells than SMA+ cells expressed interleukin-1 alpha protein. IL-1 beta expression patterns in SMA+ and SMA- stromal cells was similar to that of IL-1 alpha after PRK. Previous studies have demonstrated that IL-1 alpha or IL-1 beta triggers myofibroblast apoptosis in vitro, depending on the available concentration of apoptosis-suppressive TGFO. This study demonstrates that SMA- cells such as corneal fibroblasts, keratocytes, or inflammatory cells may produce IL-1 alpha and/or IL-1 beta that could act in paracrine fashion to regulate myofibroblast apoptosis-especially in the region where there is haze in the cornea after PRK was performed and SMA+ myofibroblasts are present at higher density. However, some SMA+ myofibroblasts themselves produce IL-1 alpha and/or IL-1 beta, suggesting that myofibroblast viability could also be regulated via autocrine mechanisms. (C) 2010 Elsevier Ltd. All rights reserved.

Corneal myofibroblast generation from bone marrow-derived cells

The purpose of this study was to determine whether bone marrow-derived cells can differentiate into myofibroblasts, as defined by alpha-smooth muscle actin (SMA) expression, that arise in the corneal stroma after irregular phototherapeutic keratectomy and whose presence within the cornea is associated with corneal stromal haze. C578L/6J-GFP chimeric mice were generated through bone marrow transplantation from donor mice that expressed enhanced green fluorescent protein (GFP) in a high proportion of their bone marrow-derived cells. Twenty-four GFP chimeric mice underwent haze-generating corneal epithelial scrape followed by irregular phototherapeutic keratectomy (PTK) with an excimer laser in one eye. Mice were euthanized at 2 weeks or 4 weeks after PTK and the treated and control contralateral eyes were removed and cryo-preserved for sectioning for immunocytochemistry. Double immunocytochemistry for GFP and myofibroblast marker alpha-smooth muscle actin (SMA) were performed and the number of SMA+GFP+, SMA+GFP, SMA-GFP+ and SMA GFP cells, as well as the number of DAPI+ cell nuclei, per 400x field of stroma was determined in the central, mid-peripheral and peri-limbal cornea. In this mouse model, there were no SMA+ cells and only a few GFP+ cells detected in unwounded control corneas. No SMA+ cells were detected in the stroma at two weeks after irregular PTK, even though there were numerous GFP+ cells present. At 4 weeks after irregular PTK, all corneas developed mild to moderately severe corneal haze. In each of the three regions of the corneas examined, there were on average more than 9x more SMA+GFP+ than SMA+GFP myofibroblasts. This difference was significant (p < 0.01). There were significantly more (p < 0.01) SMA GFP+ cells, which likely include inflammatory cells, than SMA+GFP+ or SMA+GFP cells, although SMA GFP cells represent the largest population of cells in the corneas. In this mouse model, the majority of myofibroblasts developed from bone marrow-derived cells. It is possible that all myofibroblasts in these animals developed from bone marrow-derived cells since mouse chimeras produced using this method had only 60-95% of bone marrow-derived cells that were GFP+ and it is not possible to achieve 100% chimerization. This model, therefore, cannot exclude the possibility of myofibroblasts also developed from keratocytes and/or corneal fibroblasts. (C) 2010 Elsevier Ltd. All rights reserved.

Reprint of ""Dynamics of the expression of intermediate filaments vimentin and desmin during myofibroblast differentiation after corneal injury""

Previous studies have suggested that abnormal corneal wound healing in patients after photorefractive keratectomy (PRK) is associated with the appearance of myofibroblasts in the stroma between two and four weeks after surgery. The purpose of this study was to examine potential myofibroblast progenitor cells that might express other filament markers prior to completion of the differentiation pathway that yields alpha-smooth muscle actin (SMA)-expressing myofibroblasts associated with haze localized beneath the epithelial basement membrane after PRK. Twenty-four female rabbits that had -9 diopter PRK were sacrificed at 1 week, 2 weeks, 3 weeks or 4 weeks after surgery. Corneal rims were collected, frozen at -80 degrees C, and analyzed by immunocytochemistry using anti-vimentin, anti-desmin, and anti-SMA antibodies. Double immunostaining was performed for the co-localization of SMA with vimentin or desmin with SMA. An increase in vimentin expression in stromal cells is noted as early as 1 week after PRK in the rabbit cornea. As the healing response continues at two or three weeks after surgery, many stromal cells expressing vimentin also begin to express desmin and SMA. By 4 weeks after the surgery most, if not all, myofibroblasts express vimentin, desmin and SMA. Generalized least squares regression analysis showed that there was strong evidence that each of the marker groups differed in expression over time compared to the other two (p < 0.01). Intermediate filaments - vimentin and desmin co-exist in myofibroblasts along with SMA and may play an important role in corneal remodeling after photorefractive keratectomy. The earliest precursors of myofibroblasts destined to express SMA and desmin are detectible by staining for vimentin at 1 week after surgery. (C) 2009 Elsevier Ltd. All rights reserved.

Effect of Femtosecond Laser Energy Level on Corneal Stromal Cell Death and Inflammation

PURPOSE: To analyze the effects of variations in femtosecond laser energy level on corneal stromal cell death. and inflammatory cell influx following flap creation in a rabbit model. METHODS: Eighteen rabbits were stratified in three different groups according to level of energy applied for flap creation (six animals per group). Three different energy levels were chosen for both the lamellar and side cut; 2.7 mu J (high energy), 1.6 mu J (intermediate energy), and 0.5 mu J (low energy) with a 60 kHz, model II, femtosecond laser (IntraLase). The opposite eye of each rabbit served as a control. At the 24-hour time point after surgery, all rabbits were euthanized and the comeoscleral rims were analyzed for the levels of cell death and inflammatory cell influx with the terminal uridine deoxynucleotidyl transferase dUTP-nick end labeling (TUNEL) assay and immunocytochemistry for monocyte marker CD11b, respectively. RESULTS: The high energy group (31.9 +/- 7.1 [standard error of mean (SEM) 2.9]) had significantly more TUNEL positive cells in the central flap compared to the intermediate (22.2 +/- 1.9 [SEM 0.8], P=.004), low (17.9 +/- 4.0 [SEM 1.6], P <= .001), and control eye (0.06 +/- 0.02 [SEM 0.009], P <= .001) groups. The intermediate and low energy groups also had significantly more TUNEL positive cells than the control groups (P <= .001). The difference between the intermediate and low energy levels was not significant (P=.56). The mean for CD11b-positive cells/400x field at the flap edge was 26.1 +/- 29.3 (SEM 11.9), 5.8 +/- 4.1 (SEM 1.6), 1.6 +/- 4.1 (SEM 1.6), and 0.005 +/- 0.01 (SEM 0.005) for high energy, intermediate energy, low energy, and control groups, respectively. Only the intermediate energy group showed statistically more inflammatory cells than control eyes (P = .015), most likely due to variability between eyes. CONCLUSIONS: Higher energy levels trigger greater cell death when the femtosecond laser is used to create corneal flaps: Greater corneal inflammatory cell infiltration is observed with higher femtosecond laser energy levels. [J Refract Surg. 2009;25:869-874.] doi:10.3928/1081597X-20090917-08

Corneal stroma PDGF blockade and myofibroblast development

Myofibroblast development and haze generation in the corneal stroma is mediated by cytokines, including transforming growth factor-beta (TGF-beta), and possibly other cytokines. This study examined the effects of stromal PDGF-beta blockade on the development of myofibroblasts in response to -9.0 diopter photorefractive keratectomy in the rabbit. Rabbits that had haze generating photorefractive keratectomy (PRK, for 9 diopters of myopia) in one eye were divided into three different groups: stromal application of plasmid pCMV.PDGFRB.23KDEL expressing a subunit of PDGF receptor b (domains 2-3, which bind PDGF-B), stromal application of empty plasmid pCMV, or stromal application of balanced salt solution (BSS). The plasmids (at a concentration 1000 ng/mu l) or BSS was applied to the exposed stroma immediately after surgery and every 24 h for 4-5 days until the epithelium healed. The group treated with pCMV.PDGFRB.23KDEL showed lower alpha SMA+ myofibroblast density in the anterior stroma compared to either control group (P <= 0.001). Although there was also lower corneal haze at the slit lamp at one month after surgery, the difference in haze after PDGF-B blockade was not statistically significant compared to either control group. Stromal PDGF-B blockade during the early postoperative period following PRK decreases stromal alpha SMA+ myofibroblast generation. PDGF is an important modulator of myofibroblast development in the cornea. (C) 2008 Elsevier Ltd. All rights reserved.

EFFECT OF THE TEMPERATURE AND pH ON METHANOL RELEASE IN COFFEE BREW SWEETENED WITH ASPARTAME

Methanol is an alcohol which is metabolized to folmaldehyde in humans. It is a very toxic substance, responsible for blindness in cases of methanol intoxication. This study shows the production of methanol when aspartame is used to sweeten coffee brew. The temperature versus pH binomium was also tested. When assayed at 90 degrees C coffee brew+aspartame and aspartame solution showed an increase in methanol release of 17.8 and 19.3%, respectively, as compared with coffee brew. At 180 degrees C, the increase was 32.5 and 26.3%, respectively. Our data revealed a protective effect of the pH of coffee on the degradation of aspartame and formation of methanol; an important fact, mainly for specific populations that use aspartame, like diabetics.

Epidemiologic aspects and clinical outcome of fungal keratitis in southeastern Brazil

PURPOSE. Fungal keratitis (FK) is a sight-threatening disease, more prevalent in developing regions. The present retrospective study was conducted in order to evaluate the epidemiologic and clinical aspects and the progression of FK in patients treated at two ophthalmologic reference centers in Southeast Brazil. METHODS. The charts of patients with infectious keratitis treated between 2000 and 2004 were reviewed. For the 66 cases of FK confirmed by microbiological analysis, data related to patient, disease, and therapeutic approaches were obtained. RESULTS. Mean patient age was 40.7 +/- 16 years. Fifty-three were men and 13 were women. Ocular trauma occurred in 40% of cases (27). Previous medications taken by the patients were quinolone in 72.5% and antimycotics in 30%. Visual acuity (VA) at presentation was >0.3 in 16% and <0.1 in 74.5%. Penetrant keratoplasty was performed in 38% and evisceration in 15%. The causing agents were Fusarium sp in 67%, Aspergillus sp in 10.5%, and Candida sp in 10%. Medication alone resolved 39% of cases within a mean period of 24.5 +/- 12 days. Final VA was >0.3 in 28%, and <0.1 in 63%. CONCLUSIONS. Fungal keratitis presented as a disease with severe complications, predominantly among young males, and was mostly caused by filamentous fungi. The present information permits the establishment of preventive strategies. Reducing the time between onset and treatment and using more accessible specific medication would reverse the negative prognosis. (Eur J Ophthalmol 2009; 19: 355-61)