Microglial Plasticity Contributes to Recovery of Bone Marrow Mononuclear Cells during Experimental Stroke

Brain stroke is an acute neural disorder characterized by obstruction (ischemic) or rupture (hemorrhagic) of blood vessels causing neural damage and subsequent functional impairment. Its pathophysiology is complex and involves a multitude of pathological events including energetic collapse, excitotoxicity, oxidative stress, metabolic acidosis, cell death and neuroinflammation. Despite its clinical importance, there is no effective pharmacological therapies available to diminish secondary damage avowing functional deficits. Considering the failure of pharmacological approaches for stroke, cell therapy came as promising alternative. Different cell types have been investigated in different experimental models with promising results. An important issue regarding the transplantation of stem cells into the damaged CNS tissue is how the pathological environment influences the transplanted cells. It has been established that an exacerbated inflammation in the pathological environment is detrimental to the survival of the transplanted stem cells. This prompted us to develop an experimental strategy to improve the therapeutic actions of bone marrow mononuclear cells (BMMCs) transplanted into the acute phase of brain stroke by modulating microglial activation with minocycline. In this chapter, we first review the basic pathophysiology of ischemic stroke with emphasis on the role of microglia to the pathological outcome. We then review the experimental approach of modulating microglia activation in order to enhance therapeutic actions of BMMCS for experimental stroke. We suggest that such an approach may be applied as an adjuvant therapy to control excessive neuroinflammation in the pathological environment allowing acute transplants and improving therapeutic actions of different kind of stem cells

Peripheral variability and central constancy in mammalian visual system evolution

Neural systems are necessarily the adaptive products of natural selection, but a neural system, dedicated to any particular function in a complex brain, may be composed of components that covary with functionally unrelated systems, owing to constraints beyond immediate functional requirements. Some studies support a modular or mosaic organization of the brain, whereas others emphasize coordination and covariation. To contrast these views, we have analysed the retina, striate cortex (V1) and extrastriate cortex (V2, V3, MT, etc.) in 30 mammals, examining the area of the neocortex and individual neocortical areas and the relative numbers of rods and cones. Controlling for brain size and species relatedness, the sizes of visual cortical areas (striate, extrastriate) within the brains of nocturnal and diurnal mammals are not statistically different from one another. The relative sizes of all cortical areas, visual, somatosensory and auditory, are best predicted by the total size of the neocortex. In the sensory periphery, the retina is clearly specialized for niche. New data on rod and cone numbers in various New World primates confirm that rod and cone complements of the retina vary substantially between nocturnal and diurnal species. Although peripheral specializations or receptor surfaces may be highly susceptible to niche-specific selection pressures, the areal divisions of the cerebral cortex are considerably more conservative

Number and topography of cones, rods and optic nerve axons in new and old world primates

Cornell University. Departments of Psychology and Neurobiology and Behavior. Ithaca, New York, US.Universidade Federal do Pará. Centro de Ciências Biológicas. Departamento de Fisiologia. Belém, PA, Brasil.Universidade Federal do Pará. Centro de Ciências Biológicas. Departamento de Fisiologia. Belém, PA, Brasil.Cornell University. Departments of Psychology and Neurobiology and Behavior. Ithaca, New York, US.Cornell University. Departments of Psychology and Neurobiology and Behavior. Ithaca, New York, US.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Centro Nacional de Primatas. Ananindeua, PA, Brasil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brasil.To better understand the evolution of spatial and color vision, the number and spatial distributions of cones, rods, and optic nerve axon numbers were assessed in seven New World primates (Cebus apella, Saimiri ustius, Saguinus midas niger, Alouatta caraya, Aotus azarae, Calllithrix jacchus, and Callicebus moloch). The spatial distribution and number of rods and cones was determined from counts of retinal whole mounts. Optic axon number was determined from optic nerve sections by electron microscopy. These data were amassed with existing data on retinal cell number and distribution in Old World primates, and the scaling of relative densities and numbers with respect to retinal area, eye and brain sizes, and foveal specializations were evaluated. Regular scaling of all cell types was observed, with the exceptionally large, rod-enriched retina of the nocturnal owl monkey Aotus azarae, and the unusually high cone density of the fovea of the trichromatic howler monkey Alouatta caraya presenting interesting variations on this basic plan. Over all species, the lawful scaling of rods, cones, and retinal ganglion cell number is hypothesized to result from a conserved sequence of cell generation that defends retinal acuity and sensitivity over a large range of eye sizes

M and P retinal ganglion cells of the owl monkey: morphology, size and photoreceptor convergence

We have estimated photoreceptor convergence to M and P retinal ganglion cells of two closely related nocturnal (owl monkey, Aotus) and diurnal (capuchin monkey, Cebus) anthropoids. Rod convergence is higher in the owl monkey retina while cone convergence to both M and P cells are very similar in the retinas of the owl monkey and the capuchin monkey. These results indicate that during evolution, the owl monkey retina has undergone changes compatible with a more nocturnal lifestyle, but kept a cone to ganglion cell relation similar to that found in diurnal primates

T-piece versus self-inflating bag ventilation in preterm neonates at birth

Objective To verify whether the use of the T-piece resuscitator compared with the self-inflating bag in preterm infants ventilated at birth modifies survival to hospital discharge without major morbidities. Design Pragmatic prospective cohort study. Setting 20 Brazilian university hospitals of Brazilian Network on Neonatal Research. Patients were 1962 inborn infants in 2014-2015 ventilated at birth with 23-33' weeks gestation and birth weight 400-1499 g without malformations. Patients transferred until the 27th day after birth were excluded. Interventions Positive pressure ventilation at birth with T-piece resuscitator or self-inflating bag without positive end expiratory pressure valve. Intervention with ventilation followed the Brazilian Society of Pediatrics guidelines. The choice of the equipment was at the neonatologist's discretion in each delivery. The main outcome measures were survival to hospital discharge without bronchopulmonary dysplasia, severe peri-intraventricular haemorrhage and periventricular leucomalada. Logistic regression adjusted for confounding variables was applied for main outcome. Results 1456 (74%) were only ventilated with T-piece resuscitator and 506 (26%) with the self-inflating bag. The characteristics of those ventilated with T-Piece resuscitator versus self-inflating bag were birth weight 969 +/- 277 vs 941 +/- 279 g, gestational age 28.2 +/- 2.5 vs 27.8 +/- 2.7 weeks and survival to hospital discharge without major morbidities 47% vs 35%, Logistic regression adjusted for maternal characteristics, obstetric and neonatal morbidities showed that the T-piece resuscitator increased the chance of survival to hospital discharge without major morbidities (OR=1.38; 95% Cl 1.06 to 1.80; Hosmer-Lemeshow goodness of fit: 0.695). Conclusion This study is the first that highlights the effectiveness of T-piece resuscitator ventilation in improving relevant outcomes in preterm neonates.Univ Fed Sao Paulo, Div Neonatal Med, Sao Paulo, BrazilUniv Sao Paulo, Dept Pediat, Fac Med Ribeirao Preto, Ribeirao Preto, BrazilUniv Fed Maranhao, Dept Pediat, Sao Luis, BrazilUniv Estadual Campinas, Dept Pediat, Fac Ciencias Med, Campinas, SP, BrazilUniv Sao Paulo, Dept Pediat, Fac Med, Sao Paulo, BrazilUniv Estadual Paulista, Div Neonatol, Fac Med Botucatu, Botucatu, SP, BrazilFundacao Oswaldo Cruz, Div Neonatol, Rio De Janeiro, BrazilPontificia Univ Catolica Rio Grande do Sul, Dept Pediat, Hosp Sao Lucas, Fac Med, Porto Alegre, RS, BrazilUniv Fed Rio Grande do Sul, Div Neonatol, Hosp Clin Porto Alegre, Porto Alegre, RS, BrazilUniv Estado Rio de Janeiro, Dept Pediat, Hosp Univ Pedro Ernesto, Rio De Janeiro, BrazilUniv Fed Minas Gerais, Div Neonatol, Belo Horizonte, MG, BrazilUniv Fed Uberlandia, Pediat, Uberlandia, MG, BrazilMaternidade Hilda Brandao, Dept Pediat, Fac Ciencias Med Minas Gerais, Belo Horizonte, MG, BrazilUniv Sao Paulo, Sch Med, Dept Pediat, Sao Paulo, SP, BrazilHosp Estadual Sumare, Neonatal Div, Sumare, BrazilHosp Geral Pirajussara, Neonatal Unit, Taboao Da Serra, BrazilHosp Estadual Diadema, Neonatal Unit, Diadema, BrazilUniv Estadual Londrina, Dept Pediat, Hosp Univ, Curitiba, Parana, BrazilUniv Fed Parana, Dept Pediat, Hosp Clin, Curitiba, Parana, BrazilInst Med Integral Prof Fernando Figueira, Dept Pediat, Recife, PE, BrazilInst Fernandes Figueira FIOCRUZ, Dept Pediat, Rio De Janeiro, BrazilUniv Fed Sao Paulo, Div Neonatal Med, Sao Paulo, BrazilWeb of Scienc

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved