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Exploring Iris Colour Prediction And Ancestry Inference In Admixed Populations Of South America.

New DNA-based predictive tests for physical characteristics and inference of ancestry are highly informative tools that are being increasingly used in forensic genetic analysis. Two eye colour prediction models: a Bayesian classifier - Snipper and a multinomial logistic regression (MLR) system for the Irisplex assay, have been described for the analysis of unadmixed European populations. Since multiple SNPs in combination contribute in varying degrees to eye colour predictability in Europeans, it is likely that these predictive tests will perform in different ways amongst admixed populations that have European co-ancestry, compared to unadmixed Europeans. In this study we examined 99 individuals from two admixed South American populations comparing eye colour versus ancestry in order to reveal a direct correlation of light eye colour phenotypes with European co-ancestry in admixed individuals. Additionally, eye colour prediction following six prediction models, using varying numbers of SNPs and based on Snipper and MLR, were applied to the study populations. Furthermore, patterns of eye colour prediction have been inferred for a set of publicly available admixed and globally distributed populations from the HGDP-CEPH panel and 1000 Genomes databases with a special emphasis on admixed American populations similar to those of the study samples.

Evaluation of iris color stability in ocular prosthesis

Accurate iris reproduction in the fabrication of ocular prosthesis in order to match the remaining eye is a key factor to mask the loss and achieve an esthetic outcome for anophthalmic patients. This study evaluated the stability of acrylic paints used for replicating iris color in ocular prostheses by the analysis of two factors: the temperature of the acrylic resin polymerization cycle during prosthesis fabrication and the incidence of sun light, which is the main photodegrading agent undermining the longevity of ocular prostheses. An accelerated aging assay was used for both analyses. Specimens simulating the prosthetic iris in the colors blue, yellow, black, brown and green were fabricated, and were submitted to a colorimetric reading before and after undergoing the thermal conditions of acrylic resin polymerization. Next, the specimens were submitted to an artificial accelerated aging assay with ultraviolet radiation A and weekly colorimetric readings during a 3-week period. The color change (??*) values for the four specimens painted with the same color paint were averaged and the resulting values were considered for statistical analysis. Levine's test and Student's t-test were used to analyze the influence of the temperature of the polymerization cycle during prosthesis fabrication on the color stability of each acrylic resin paint. Friedman's test for three dependent samples was used for analysis of color photodegradation as function of time. Significance level was set at 0.05 for all analyses. It was observed that, after the action of the temperature of the polymerization cycle, alteration above clinically acceptable level of ??*> 3.3 was observed only for the yellow color. After the accelerated aging assay, there were statistically significant differences (p<0.05) as a function of time in the green, brown, black and blue colors. Changes were clinically acceptable for the brown and black colors; slightly above the clinically acceptable limit for the green color; and significantly high and impracticable from a clinical standpoint for the blue color. There was no statistically significant differences (p>0.05) for the yellow color, which presented color change only a little above the clinically acceptable limit. In conclusion: 1. Only the yellow color presented alterations above the clinically acceptable levels after the polymerization cycle; 2. After accelerated aging, there was no changes in the yellow color above the clinically acceptable levels; 3. For the green color, degradation was significant and slightly above the clinically acceptable levels; 4. The black, brown and blue colors presented significant alterations as function of time; the alterations of the brown and black colors were within acceptable clinical levels, while the blue color presented a more accentuated degradation over time.

Resident tissue macrophages within the normal rat iris lack immunosuppressive activity and are effective antigen-presenting cells

Despite extensive study of the numerous immunoregulatory mechanisms that contribute to the immune-privileged nature of the anterior chamber (AC) of the eye, little is known of the functional nature of antigen-presenting cells (APC) present in the tissues adjoining the AC. In the present study, we have compared the antigen-presenting capacity of dendritic cells (DC) and macrophages isolated from the normal rat iris. Whereas iris DC exhibited a potent ability to stimulate resting allogeneic T cells in MLR cultures (an in-vitro correlate of the ability to induce primary T cell responses), resident iris macrophages displayed negligible MLR-stimulatory capacity. Significantly, iris macrophages could efficiently elicit proliferation of primed antigen-specific T cells (an in-vitro correlate of the ability to act as local APC in secondary responses). This antigen-presenting activity was approximately half that of fully mature iris DC and considerably greater than that of freshly isolated iris DC. A key contributor to the effectiveness of resident iris macrophage antigen presentation was considered to be the absence of lymphocytostatic control of T cell proliferation exerted by these cells. The results indicate dichotomous but complementary roles for DC (immune surveillance) and macrophages (local antigen presentation in secondary responses) in this tissue.

Major histocompatibility complex (MHC) class II-positive dendritic cells in the rat iris - In situ development from MHC class II-negative precursors

Purpose. To examine the postnatal development of major histocompatibility complex (MHC) class II-positive dendritic cells (DC) in the iris of the normal rat eye. Methods. Single-and double-color immunomorphologic studies were performed on whole mounts prepared from rat iris taken at selected postnatal ages (2 to 3 days to 78 weeks). Immunopositive cells were enumerated, using a quantitative light microscope, and MHC class II expression on individual cells was assessed by microdensitometric analysis. Results. Major histocompatibility class II-positive DCs in the iris developed in an age-dependent manner and reached adult-equivalent density and structure at approximately 10 weeks of age, considerably later than previously described in other DC populations in the rat. In contrast, the anti-rat DC monoclonal antibody OX62 revealed a population of cells present at adult-equivalent levels as early as 3 weeks after birth. Dual-color immunostaining and microdensitometric analysis demonstrated that during postnatal growth, development of the network of MHC class II-positive DCs was a consequence of the progressive increase in expression of MHC class II antigen by OX62-positive cells. Conclusions. During postnatal growth, the DC population of the iris develops initially as an OX62-positive-MHC class II-negative population, which then develops increasing MHC class II expression in situ and finally resembles classic DC populations in other tissue sites. Maturation of the iris DC population is temporally delayed compared with time to maturation in other tissue sites in the rat.

Tuning Iris Recognition for Noisy Images

The use of iris recognition for human authentication has been spreading in the past years. Daugman has proposed a method for iris recognition, composed by four stages: segmentation, normalization, feature extraction, and matching. In this paper we propose some modifications and extensions to Daugman's method to cope with noisy images. These modifications are proposed after a study of images of CASIA and UBIRIS databases. The major modification is on the computationally demanding segmentation stage, for which we propose a faster and equally accurate template matching approach. The extensions on the algorithm address the important issue of pre-processing that depends on the image database, being mandatory when we have a non infra-red camera, like a typical WebCam. For this scenario, we propose methods for reflection removal and pupil enhancement and isolation. The tests, carried out by our C# application on grayscale CASIA and UBIRIS images show that the template matching segmentation method is more accurate and faster than the previous one, for noisy images. The proposed algorithms are found to be efficient and necessary when we deal with non infra-red images and non uniform illumination.

Disposición plasmática y residuos tisulares de marbofloxacina en truchas arco iris (oncorhynchus mykiss) en condiciones estivales e invernales. Plasmatic disposition and tissue residues of marbofloxacin in rainbow trouts (oncorhynchus mykiss) in summer and winter conditions

Los sistemas intensivos de producción, predisponen en los peces a la presentación de diversas enfermedades, lo que demanda el empleo de antimicrobianos para mantener la salud de los lotes de cultivo. En tal sentido es importante contar con información local en cuanto al comportamiento cinético a los efectos de determinar una adecuada dosificación de los antimicrobianos empleados y con esta información, establecer los periodos de resguardo necesarios para evitar la presencia violativa de estos fármacos en el animal destinado a consumo humano. En el presente proyecto se propone efectuar un estudio farmacocinético de concentraciones plasmáticas y tisulares alcanzadas y establecer los periodos de resguardo para marbofloxacina, antimicrobiano del cual no se tienen antecedentes regionales en cuanto a su disposición a diferentes temperaturas como las que condicionan las estaciones de verano e invierno, de marcada variación en la provincia, modificando la actividad metabólica de los peces. La concreción de este proyecto permitirá entregar conocimientos concretos y de aplicación directa en la cría intensiva de la trucha arco iris (Oncorhynchus mykiss) en diferentes condiciones ambientales, al contarse con la información necesaria para una adecuada dosificación y periodos de resguardo necesarios para evitar el residuo de este fármaco. Además, permitirá consolidar una línea de investigación dentro de la acuicultura muy poco desarrollada actualmente en el país. Intensive production systems predispose fishes to diverse diseases, which demands antimicrobial use for health maintenance in the lots of culture. In such sense it is important to have local information of the kinetic behavior to determine a suitable dosing of the antimicrobials employed, and on this information, to establish withdrawal periods to avoid the violative presence of these drugs in animals for human consumption. The present project will carry out a pharmacokinetic study of plasmatic and tissue concentrations to establish the withdrawal period for marbofloxacin, being known that temperature, modify the metabolic activity of the fish, and there are no local antecedents of disposition at different temperatures in summer and winter for this antimicrobial. The concretion of this project will allow to give concrete knowledge of direct application in intensive production of rainbow trout (Oncorhynchus mykiss), in different environmental conditions, counting with the necessary information for a suitable dosification and withdrawal periods to avoid residues of this drug. In addition, it will allow to consolidate an investigation line in acuiculture, not much developed in our country.

Fenilefrina intracamerular en el síndrome del iris flácido intraoperatorio

La incidència d’hipertròfia benigna de pròstata és aproximadament d’un 50 % en pacients majors de 50 anys. La Tamsulosina és el medicament més prescrit per aquesta dolència i la principal causa del síndrome d’iris flàccid intraoperatori a la cirurgia de cataractes. Els nostres dos estudis han sigut; per una banda, avaluar la toxicitat corneal i afectació cardíaca de Fenilefrina intracamerular a una concentració de 2,5% respecte la pauta de dilatació tòpica estàndard al nostre centre, i per l’altra, comparar l’ efectivitat i diferència al recompte endotelial de Fenilefrina intracamerular a una concentració de 2,5% respecte a una altra concentració del 1,66 %, mesurant els seus efectes en diverses variables.

Notch signaling in the pigmented epithelium of the anterior eye segment promotes ciliary body development at the expense of iris formation.

The ciliary body and iris are pigmented epithelial structures in the anterior eye segment that function to maintain correct intra-ocular pressure and regulate exposure of the internal eye structures to light, respectively. The cellular and molecular factors that mediate the development of the ciliary body and iris from the ocular pigmented epithelium remain to be fully elucidated. Here, we have investigated the role of Notch signaling during the development of the anterior pigmented epithelium by using genetic loss- and gain-of-function approaches. Loss of canonical Notch signaling results in normal iris development but absence of the ciliary body. This causes progressive hypotony and over time leads to phthisis bulbi, a condition characterized by shrinkage of the eye and loss of structure/function. Conversely, Notch gain-of-function results in aniridia and profound ciliary body hyperplasia, which causes ocular hypertension and glaucoma-like disease. Collectively, these data indicate that Notch signaling promotes ciliary body development at the expense of iris formation and reveals novel animal models of human ocular pathologies.

The sign of the Cross of Andreas in the iris and Diabetes Mellitus: a longitudinal study

OBJECTIVETo compare the development of diabetes mellitus in subjects with and without the sign of the Cross of Andreas in the iris over a period of four years.METHODA prospective, descriptive study of quantitative approach. This cohort study had 91 patients without the disease, with and without the signal. The monitoring was conducted by means of the records in medical charts.RESULTSAt the end of the research, 28.2% of the group with the sign of the Cross of Andreas was diagnosed with diabetes and 56.5% had two or more episodes of impaired glucose tolerance. In the group without the sign, 4.4% was diagnosed with the disease and 24.5% had two or more episodes of glucose intolerance. There was a statistically significant difference between the groups regarding the development of the disease and glucose intolerance.CONCLUSIONThe group with the Cross of Andreas developed more glucose intolerance and diabetes than the group without the sign.

Impairment of JCV-specific T-cell response by corticotherapy: Effect on PML-IRIS management?

OBJECTIVE: To investigate the impact of corticosteroids (CS) on the viral-specific T-cell response, in particular the JC virus (JCV)-specific one, in an attempt to determine the optimal timing of CS in the management of progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome (PML-IRIS). METHODS: A blood draw was performed before and 7 days after the administration of IV CS to 24 patients with relapsing multiple sclerosis (MS). The phenotypic pattern of T cells was determined by CCR7 and CD45RA. To assess the impact of CS treatment on proliferative response of JCV-, influenza-, and Epstein-Barr virus (EBV)-specific T cells, a thymidine incorporation proliferation assay was performed. An intracellular cytokine staining assay was performed to determine the effect of CS treatment on the production of cytokine by virus-specific T cells. JCV T-cell assays were performed only in JCV-infected patients with MS as detected by serologies (Stratify) or detection of JCV DNA in the urine by PCR. RESULTS: CS led T cells, CD4+ and CD8+, toward a less differentiated phenotype. There was a significant decrease of EBV-, influenza-, and JCV-specific T-cell proliferative response upon CS treatment. There was a significant decrease in the frequency of interferon (IFN) γ- and tumor necrosis factor (TNF) α-producing JCV-specific CD8+ T cells, but not EBV- or influenza-specific CD4+ or CD8+ T cells. CONCLUSIONS: CS have a profound impact on the virus-specific T-cell response, especially on JCV, suggesting that when CS are considered, they should not be given before the onset of clinical or radiologic signs of IRIS. Studies addressing directly patients with MS with natalizumab-caused PML are warranted. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that methylprednisolone treatment decreases the frequency of JCV-specific CD8+ T cells producing IFN-γ and TNFα, impairing control of JCV, suggesting this should be used to treat but not to prevent PML-IRIS. No clinical outcomes were measured.