Papers by ANA PAULINA PEREZ RAMIREZ
Histology and histopathology, 2005
To determine the distribution of NPY and TH human choroidal innervation, choroidal whole-mounts w... more To determine the distribution of NPY and TH human choroidal innervation, choroidal whole-mounts were processed for indirect immunofluorescence. An antibody to a component of the neuronal cytoskeleton, neurofilament 200 kDa (NF-200) was used to identify neurons and axons. A double immunostaining was performed, antibodies against NF-200 being combined with antibodies against neuropeptide Y (NPY) and tyroxine hydroxylase (TH). Fibers containing both NPY and TH were distributed in three plexuses, one in the suprachoroid large-sized vessel layer, and two in the medium-sized vessel layer. Intrinsic choroidal neurons (ICNs) containing NPY and TH were observed in the suprachoroid. The TH(+) ICNs were located in the medium-sized vessel layer. Overall, NPY(+) and TH(+) ICNs were more frequent in the central temporal area, both in isolation and forming microganglia. We also detected small spindle elements intensely immunoreactive to TH(+) and distributed mainly in the suprachoroid from the equ...
2010 18th European Signal Processing Conference, 2010
Recent work on dimensionality reduction using Cauchy random projections has emerged for applicati... more Recent work on dimensionality reduction using Cauchy random projections has emerged for applications where ℓ<sub>1</sub> distance preservation is preferred. An original sparse signal b ϵ ℝ<sup>n</sup> is multiplied by a Cauchy random matrix <b>R</b> ϵ ℝ<sup>n×k</sup> (k≪n), resulting in a projected vector c ϵ ℝ<sup>k</sup>. Two approaches for fast recover of b from the Cauchy vector c are proposed. The two algorithms are based on a regularized coordinate-descent Myriad regression using both ℓ<sub>0</sub> and convex relaxation as sparsity inducing terms. The key element is to start, in the first iteration, by finding the optimal estimate value for each coordinate, and selectively updating only the coordinates with rapid descent in subsequent iterations. For the particular case of the ℓ<sub>0</sub> regularized approach, an approximation function for the ℓ<sub>0</sub>-norm is given due to it...
Los micoplasmas pertenecen a la clase Mollicutes. Descienden, a traves de la reduccion del cromos... more Los micoplasmas pertenecen a la clase Mollicutes. Descienden, a traves de la reduccion del cromosoma, de las bacterias gram positivas, siendo las formas de vida mas pequena auto-replicante. Su tamano del genoma, extremadamente pequeno, impone unos requerimientos nutricionales complejos, dependiendo de suplementos externos de precursores biosinteticos. Los micoplasmas patogenos son los microorganismos mas dificiles de aislar de muestras clinicas. Por lo tanto, para conseguir que los micoplasmas patogenos crezcan independientemente, hay que tener en cuenta su naturaleza dificil y su dependencia intima con el hospedador. Esta tesis se ha centrado en el estudio de medios de cultivo para micoplasmas. En una primera parte se desarrollo un medio semidefinido si suero animal (MWS) carente de albumina serica, con la finalidad de poder utilizarse en la produccion de vacunas frente a micoplasmosis. Se consiguio la replicacion, tras un periodo de adaptacion en dicho medio, de cepas de Mycoplasma mycoides subsp. Mycoides tipo LC, M.m.subsp.capri, M.capricolum subsp.capricolum, M.agalactiae y M.arginini. Hasta ahora ningun unico medio de cultivo ha sido apropiado para todas las especies de micoplamas por razones que no estan todavia claras. Dado el inconveniente que resulta disponer de diferentes formulas para el crecimiento de un grupo de micoplasmas heterogeneos(micoplasmas de origen porcino, bovino, caprino, ovino, aviar), en una segunda parte del estudio, se desarrollo un medio de aislamiento con este fin, el medio SP4-II. Dicho medio dio unos resultados muy satisfactorios, tanto en el cultivo de cepas como en aislamientos primarios de las especies estudiadas, por lo que se puede recomendar su utilizacion como medio de aislamiento general para las especies clasicas de micoplasmas(micoplasma y acholeplasmas).
Detection of Ureaplasma spp. in pig lungs with lesions consistent with swine enzootic pneumonia, ... more Detection of Ureaplasma spp. in pig lungs with lesions consistent with swine enzootic pneumonia, from the western and central regions of Cuba Detección de Ureaplasma spp. en pulmones de cerdos, con lesiones compatibles a la neumonía enzoótica porcina, procedentes de la región occidental y central de Cuba
A combined vaccine against Mycoplasma agalactiae and Mycoplasma mycoides subsp. mycoides (large c... more A combined vaccine against Mycoplasma agalactiae and Mycoplasma mycoides subsp. mycoides (large colony type) was developed using inactivated strains selected in previous characterization studies. Phenol was used as inactivating agent and aluminium hydroxide was added as adjuvant. The present study was designed to evaluate the specific humoral immune response to these two mycoplasma species shown by lambs and goat kids. One group of 15 Pelibuey lambs and one group of 8 Canary goat kids received two injections of vaccine at the ages 45 and 70 days and were monitored until they were 120 days old. Antibody titres were determined by indirect ELISA. Lambs showed lower antibody levels (expressed as ODs) to both antigens than goat kids althought significantly differences were only registered to M. agalactiae antigen (P<0.005).
Revista Venezolana de Oncologia
SUMMARY OBJECTIVE: Compare infiltrante lobulillar carcinoma and ductal carcinoma in long-term fol... more SUMMARY OBJECTIVE: Compare infiltrante lobulillar carcinoma and ductal carcinoma in long-term follow up as stage surgical treatment, neoadyuvante, adjuvant therapy. METHODS: we studied in CECLINES database 841 patients; lobulillar represents 7.25 % (61) and 51.24 % ductal (431). The overall follow up was up to twenty two years with an average of five years. RESULTS: The overall survival for lobulillar was 68.1 % and for ductal 60.9 % (P=0.772), the survival according to state was: I lobulillar 96.3 % ductal 90.5, II 94.4 % vs. 88.4 III 90.5 and 83.2 respectively (P=0.023). Estrogen receptors positive expression for lobulillar compared to ductal was 87.7 % vs. 74.7 %, (P=0.031) and its survival 96.9 % vs. 94.0 % (P=0.033). The breast conserving surgery for lobulillar compared to ductal was 57.4 % vs. 63.2 % (P=0.949) survival 85.4 % vs. 82.9 % (P=0.001). The survival reported for patients with lobulillar who received neoadyuvante chemotherapy adjuvant chemotherapy radiotherapy and adjuvant hormonotherapy compared to ductal was 93.4 % 91.3 %, 91.5 % 89.7 %, 92.5 % 89.8 % 92.5 % 88.4 %, respectively P<0.05. CONCLUSIONS: The overall survival is equal, survival favors. The lobulillar have more positive receptors and survival is better. The tendency to conservative treatment in lobulillar is increasingly. Given the hormonal profile and survival according to estrogen receptors patients with ILC, are probably good candidates to participate in neoadyuvante hormone therapy protocols. Usually the treatment is the same or similar for both groups.
Journal of Ophthalmology, 2015
Purpose. To analyze in mild Alzheimer’s disease (MAD) patients, GDS-4 (Reisberg Scale), whether o... more Purpose. To analyze in mild Alzheimer’s disease (MAD) patients, GDS-4 (Reisberg Scale), whether or not some psychophysical tests (PTs) support OCT macular findings in the same group of MAD patients reported previously.Methods. Twenty-three MAD patients and 28 age-matched control subjects with mean Mini Mental State Examination of 23.3 and 28.2, respectively, with no ocular disease or systemic disorders affecting vision were included. Best-corrected visual acuity (VA), contrast sensitivity (CS) (3, 6, 12, and 18 cpds), color perception (CP), and perception digital test (PDT) were tested in one eye of each patient.Results. In comparison with the controls, MAD patients presented (i) a significant decrease in VA, PDT, and CS for all spatial frequencies analyzed, especially the higher ones, and (ii) a significant increase in unspecific errors on the blue axis (P<0.05in all instances). In MAD patients, a wide aROC curve was plotted in all PTs.Conclusions. In MAD, CS, VA, and the tritan...
European Journal of Ophthalmology, 2015
Purpose To compare variations in surface morphology, as studied by scanning electron microscopy (... more Purpose To compare variations in surface morphology, as studied by scanning electron microscopy (SEM), of explanted intraocular lenses (IOLs) concerning the cause leading to the explantation surgery. Methods In this prospective multicenter study, explanted IOLs were analyzed by SEM and energy-dispersive X-ray spectroscopy. The IOLs were explanted in the centers of the research group from 2006 to 2012. The primary procedure was phacoemulsification in all cases. Results The study evaluated 40 IOLs. The main causes for explantation were IOL dislocation, refractive error, and IOL opacification. Those explanted due to dislocation demonstrated calcifications in 8 lenses (50%), salt precipitates in 6 cases (37.5%), and erythrocytes and fibrosis/fibroblasts in 2 cases (12.5%). In the refractive error cases, the SEM showed proteins in 5 cases (45.5%) and salt precipitates in 4 lenses (36.4%). In IOL opacification, the findings were calcifications in 2 of the 3 lenses (66.6%) and proteins in ...
Compressive Sensing IV, 2015
Traditional methods in seismic acquisition require sources and geophones that are uniformly locat... more Traditional methods in seismic acquisition require sources and geophones that are uniformly located along a spatial line, using the Nyquist sampling rate. Depending on the area to be explored, it can be necessary to use seismic surveys with large offsets, or decrease the separation between adjacent geophones to improve the resolution, which generates very high volumes of data. It makes the exploration process more difficult and particularly expensive. This work presents the reconstruction of a compressive set of seismic traces acquired using the compressive sensing paradigm where the pair of sources and geophones are randomly located along the spatial line. The recovery of the wavefield from compressive measurements is feasible due to the capabilities of Curvelets on representing wave propagators with only a small set of coefficients. The method first uses the compressive samples to find a sparse vector representation of each pixel in a 2-D Curvelet dictionary. The sparse vector representation is estimated by solving a sparsity constrained optimization problem using the Gradient Projection for Sparse Reconstruction (GPSR) method. The estimated vector is then used to compute the seismic velocity profiles via acoustic Full Waveform Inversion (FWI). Simulations of the reconstructed image gathers and the resulting seismic velocity profiles illustrate the performance of the method. An improvement in the resulting images is obtained in comparison with traditional F-K filtering used in seismic data processing when traces are missing.
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Archivos de la Sociedad Española de Oftalmología, 2006
To compare findings of normal angles with those from primary congenital glaucoma in order to clar... more To compare findings of normal angles with those from primary congenital glaucoma in order to clarify the pathogenic mechanisms of the disease and to explain the success of surgical treatment in some of these patients. Adult normal eyes from cadavers and fragments of surgical trabeculectomies from patients with primary congenital glaucoma previously treated with goniotomy were studied. Eyes were processed for examination using light microscopy and scanning electron microscopy techniques. The following was evident in congenital glaucoma: 1) high iris insertion; 2) no observable pre-trabecular membrane, but enlarged trabeculae with diminished inter-trabecular spaces; 3) Schlemm's canal (SC) apparently normal, with vacuoles in the wall indicating normal functioning; 4) sectioning of the abnormal trabecular tissue during goniotomy allowed repositioning of the angle structures and hence the appearance of the angular recess. Anomalies of the trabecular structures in primary congenital ...
Archivos de la Sociedad Española de Oftalmología, 2001
To study the rabbit retina astrocytes by using immunofluorescence techniques together with the co... more To study the rabbit retina astrocytes by using immunofluorescence techniques together with the confocal microscopy. The rabbit retinas were processed with an anti-glial fibrillary acidic protein (anti-GFAP) for astrocyte detection and with propidium lobide for nuclear staining. Confocal microscopy allows for three-dimensional reconstruction of astroglial cells, the performance of double staining procedures with superposition of images corresponding to each chromogen, the exchange of observation axes for each slide and finally the performance of serial optic sections that indicate the exact cell location and their relationship with adjacent structures, eliminating the background signals. The confocal microscopy provides detailed information about tridimensional morphology and the location of the astrocytes in the rabbit retina. The astrocytes associated with the nerve fiber bundles are located in the nerve fiber layer. The type III perivascular astrocytes are located between the intr...
Archivos de la Sociedad Española de Oftalmología, 2000
A study of human eyes with non-arteritic ischaemic optic neuropathy (NAION) to determine whether ... more A study of human eyes with non-arteritic ischaemic optic neuropathy (NAION) to determine whether there is apoptosis and whether this is accompanied by cell necrosis mechanisms. Transmission electron microscopy was used to examine the retinas of eyes with NAION. There was a large number of apoptotic ganglion cells. The lesion was not confined to this retinal layer but also affected the inner nuclear layer, where Müller glia with fagocytic capacity were detected. In this layer apoptosis alternated with necrosis in all of the cell types existing in this level: bipolar cells, amacrine cells and horizontal cells. The outer nuclear layer can also suffer lesion, essentially by induction of choroid ischaemia to that level. Again, apoptosis was observed at the photoreceptor level, where there was also death by heterophagy, although this was less frequent. The behaviour of NAION in humans is similar to that found in experimental models. Apoptosis mechanisms develop, alternating with cell necr...
Revista española de fisiología, 1991
The presence of atrial natriuretic factor (ANF) in choroid, retina and ciliary body of rabbit eye... more The presence of atrial natriuretic factor (ANF) in choroid, retina and ciliary body of rabbit eyes has been studied. The peptide was extracted by reverse phase chromatography using Sep-Pak C18 cartridges. Immunoreactive ANF (Ir-ANF) was measured by a specific RIA. In the choroid, retina and ciliary body the ir-ANF concentrations were 444 +/- 94, 67 +/- 12 and 223 +/- 75 pg/g tissue weight (n = 16), respectively. The biological activity of the acid extract ANF was evaluated by a 125I-ANF binding assay to a retinal particulate preparation. Results demonstrate the existence of biological active ANF in choroid, retina and ciliary body of rabbit eyes. The presence of ANF and its specific receptors in the ocular tissues suggests that this hormone might play a physiological role in the intraocular fluid homeostasis.
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Papers by ANA PAULINA PEREZ RAMIREZ