Impact of changing oxygenation policies on retinopathy of prematurity in a neonatal unit in Argentina.

AIMS: To assess the impact of different oxygenation policies on the rate and severity of retinopathy of prematurity (ROP). METHODS: Between January 2003 and December 2006, infants of 1500 g birthweight (BW) or less and/or 32 weeks gestational age (GA) or less, and larger, more mature infants with risk factors for ROP were examined through three different time periods: period 1: high target oxygen saturation levels (88-96%) and treatment at threshold ROP; period 2: low target oxygen saturation levels (83-93%) and treatment at threshold ROP; period 3: low target oxygen saturation and treatment at type 1 ROP. RESULTS: Type 1 ROP was detected more frequently in babies of 32 weeks GA or less (50/365, 13.7%) than in more mature babies (15/1167, 1.3%; p<0.001). The rate of type 1 ROP in period 1 was 6.9%; period 2, 3.6% and period 3, 1.8%. Rates of stage 3 ROP declined over time in both BW/GA groups (from 9.0% to 4.1% to 2.0%) as did rates of plus disease (from 7.5% to 3.6% to 1.8%). Mean BW and GA declined from period 1 to period 3, and death rates remained unchanged. 74.4% of babies received all the examinations required; 48.1% of treatments were undertaken after discharge from the neonatal unit. CONCLUSIONS: Lower target oxygen saturation was associated with a lower rate of severe ROP without increasing mortality, and changed the characteristics of affected babies. Screening criteria need to remain wide enough to identify all babies at risk of ROP needing treatment

Administration of a peptide inhibitor of alpha4-integrin inhibits the development of experimental autoimmune uveitis

Recruitment of lymphocytes into the retina and to the vitreous during the development of experimental autoimmune uveitis (EAU) is governed by factors such as the state of activation of inflammatory cells and the repertoire of adhesion molecules expressed by the local vascular endothelia. alpha4 Integrins and their receptors play an important role during homing of cells to the inflammatory site. In the present study, the effect of alpha4-integrin inhibitor on the development of EAU was investigated.Fil: Martín, Andrea P.. Universidade de Sao Paulo; BrasilFil: Vieira de Moraes, Luciana. Universidade de Sao Paulo; BrasilFil: Tadokoro, Carlos E.. Universidade de Sao Paulo; BrasilFil: Commodaro, Alessandra G.. Universidade de Sao Paulo; BrasilFil: Urrets Zavalia, Enrique. Universidad Catolica de Córdoba. Facultad de Medicina. Clinica Universitaria Reina Fabiola; ArgentinaFil: Rabinovich, Gabriel Adrián. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Urrets Zavalía, Julio Alberto. Universidad Catolica de Córdoba. Facultad de Medicina. Clinica Universitaria Reina Fabiola; ArgentinaFil: Rizzo, Luiz V.. Universidade de Sao Paulo; Brasil. Fundação Zerbini; BrasilFil: Serra, Horacio Marcelo. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentin

Effect of chondroitin sulfate on intraocular pressure in rats

PURPOSE: To study the effect of intracameral injections of chondroitin sulfate (CS) on intraocular pressure (IOP), retinal function, and histology in rats. METHODS: Acute or chronic injections of CS were performed unilaterally in the rat anterior chamber, whereas the contralateral eye was injected with vehicle. IOP was daily or weekly assessed by a tonometer. Retinal function was assessed by scotopic electroretinography (ERG) and the visual pathway by flash visual evoked potentials (VEPs), whereas the retinal and optic nerve head structure were examined by histologic analysis. RESULTS: A single injection of 8 mg (but not 2 or 4 mg) CS induced a significant increase of IOP. The increase of IOP induced by a single injection of 8 mg CS lasted for 7 days, whereas chronic (weekly) administration during 10 weeks induced a significant and sustained increase in IOP compared with eyes injected with vehicle. A significant decrease of scotopic ERG a- and b- wave amplitude was observed after 6 and 10 weeks of CS administration. Moreover, a significant decrease in scotopic flash VEP N2-P2 component amplitude was observed in eyes treated with CS for 6 and 10 weeks. A significant loss of ganglion cell layer cells and optic nerve axons was observed in eyes receiving CS for 10 weeks. CONCLUSIONS: These results suggest that exogenous CS simulates the accumulation of CS in primary open-angle glaucoma and that increased amounts of CS could play a key role in the IOP dysregulation characteristic of glaucoma.Fil: Belforte, Nicolás Adalberto. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Neuroquímica Retiniana y Oftalmología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; ArgentinaFil: Sande Casal, Pablo Horacio. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Neuroquímica Retiniana y Oftalmología Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de Zavalia, Nuria Maria Asuncion. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Neuroquímica Retiniana y Oftalmología Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Knepper, Paul A.. University of Illinois; Estados UnidosFil: Rosenstein, Ruth Estela. Universidad de Buenos Aires. Facultad de Medicina. Laboratorio de Neuroquímica Retiniana y Oftalmología Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Bioquímica Humana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentin

Mapping the co-localization of the circadian proteins PER2 and BMAL1 with enkephalin and substance P throughout the rodent forebrain

Despite rhythmic expression of clock genes being found throughout the central nervous system, very little is known about their function outside of the suprachiasmatic nucleus. Determining the pattern of clock gene expression across neuronal subpopulations is a key step in understanding their regulation and how they may influence the functions of various brain structures. Using immunofluorescence and confocal microscopy, we quantified the co-expression of the clock proteins BMAL1 and PER2 with two neuropeptides, Substance P (SubP) and Enkephalin (Enk), expressed in distinct neuronal populations throughout the forebrain. Regions examined included the limbic forebrain (dorsal striatum, nucleus accumbens, amygdala, stria terminalis), thalamus medial habenula of the thalamus, paraventricular nucleus and arcuate nucleus of the hypothalamus and the olfactory bulb. In most regions examined, BMAL1 was homogeneously expressed in nearly all neurons (~90%), and PER2 was expressed in a slightly lower proportion of cells. There was no specific correlation to SubP- or Enk- expressing subpopulations. The olfactory bulb was unique in that PER2 and BMAL1 were expressed in a much smaller percentage of cells, and Enk was rarely found in the same cells that expressed the clock proteins (SubP was undetectable). These results indicate that clock genes are not unique to specific cell types, and further studies will be required to determine the factors that contribute to the regulation of clock gene expression throughout the brain

mTOR signaling in VIP neurons regulates circadian clock synchrony and olfaction

Mammalian/mechanistic target of rapamycin (mTOR) signaling controls cell growth, proliferation, and metabolism in dividing cells. Less is known regarding its function in postmitotic neurons in the adult brain. Here we created a conditional mTOR knockout mouse model to address this question. Using the Cre-LoxP system, the mTOR gene was specifically knocked out in cells expressing Vip (vasoactive intestinal peptide), which represent a major population of interneurons widely distributed in the neocortex, suprachiasmatic nucleus (SCN), olfactory bulb (OB), and other brain regions. Using a combination of biochemical, behavioral, and imaging approaches, we found that mice lacking mTOR in VIP neurons displayed erratic circadian behavior and weakened synchronization among cells in the SCN, the master circadian pacemaker in mammals. Furthermore, we have discovered a critical role for mTOR signaling in mediating olfaction. Odor stimulated mTOR activation in the OB, anterior olfactory nucleus, as well as piriform cortex. Odor-evoked c-Fos responses along the olfactory pathway were abolished in mice lacking mTOR in VIP neurons, which is consistent with reduced olfactory sensitivity in these animals. Together, these results demonstrate that mTOR is a key regulator of SCN circadian clock synchrony and olfaction

Characterization of structure and function of the mouse retina using pattern electroretinography, pupil light reflex, and optical coherence tomography

Objective  To perform in vivo analysis of retinal functional and structural parameters in healthy mouse eyes. Animal Studied  Adult C57BL/6 male mice (n = 37). Procedures  Retinal function was evaluated using pattern electroretinography (pERG) and the chromatic pupil light reflex (cPLR). Structural properties of the retina and nerve fiber layer (NFL) were evaluated using spectral-domain optical coherence tomography (SD-OCT). Results  The average pERG amplitudes were found to be 11.2 ± 0.7 μV (P50-N95, mean ± SEM), with an implicit time for P50-N95 interval of 90.4 ± 5.4 ms. Total retinal thickness was 229.5 ± 1.7 μm (mean ± SEM) in the area centralis region. The thickness of the retinal nerve fiber layer (mean ± SEM) using a circular peripapillary retinal scan centered on the optic nerve was 46.7 ± 0.9 μm (temporal), 46.1 ± 0.9 μm (superior), 45.8 ± 0.9 μm (nasal), and 48.4 ± 1 μm (inferior). The baseline pupil diameter was 2.1 ± 0.05 mm in darkness, and 1.1 ± 0.05 and 0.56 ± 0.03 mm after stimulation with red (630 nm, luminance 200 kcd/m2) or blue (480 nm, luminance 200 kcd/m2) light illumination, respectively. Conclusions  Pattern electroretinography, cPLR and SD-OCT analysis are reproducible techniques, which can provide important information about retinal and optic nerve function and structure in mice

Chapter 10. The Impact of Spanish-American Literature in Translation on U.S. Latino Literature

The presence, impact and influence of Spanish-American literature and culture in the United States are undeniable. Emily Hicks (1991) calls it “a cannibalizing pull” from America’s “southern backyard.” But today, this cannibalizing pull is coming from right within the U.S.—from the 27 million Puerto Ricans, Mexican Americans and Cuban Americans living there. And the Latino population in the U.S. is constantly growing with the influx of immigrants from all countries in Latin America. What happ..

Distribution of proteins in the medial habenula.

<p>(A) Outlines of regions imaged in the medial habenula (HabM). Scale bar: 500 μm. (B) Localization of proteins in the dorsal portion on the HabM showing PER2 or BMAL1 in green, SubP in red, and DAPI in blue. Arrows point to cells labelled with both proteins and indicate the same cell across the row. Scale bar: 50 μm. Only the region above the dashed line were counted. (C) Pie charts representing the proportion of each labelled cell combination in the dorsal portion of the HabM. Green: PER2 or BMAL1 with DAPI only, Yellow: PER2 or BMAL1 co-expressing (Coloc), Red: SubP with DAPI only, Grey: cells identified with DAPI but not labelled with PER2, BMAL1, or SubP.</p

Distribution of proteins in the olfactory tubercle.

<p>(A) Localization of proteins in the olfactory tubercle. Enkephalin (Enk) or Substance P (SubP) are shown in red, DAPI in blue and PER2 or BMAL1 (BMAL) in green. Arrows point to cells labelled with both proteins and indicate the same cell across the row. Scale bar: 50 μm. (B) Pie charts representing the proportion of each labelled cell combination. Green: PER2 or BMAL1 with DAPI only, Yellow: co-expression of PER2 or BMAL1 with Enk or SubP (Coloc), Red: Enk or SubP with DAPI only, Grey: cells identified with DAPI but not labelled with PER2, BMAL1, Enk or SubP.</p