Inhibitors of inflammation and endogenous surfactant pool size as modulators of lung injury with initiation of ventilation in preterm sheep

<p>Abstract</p> <p>Background</p> <p>Increased pro-inflammatory cytokines in tracheal aspirates correlate with the development of BPD in preterm infants. Ventilation of preterm lambs increases pro-inflammatory cytokines and causes lung inflammation.</p> <p>Objective</p> <p>We tested the hypothesis that selective inhibitors of pro-inflammatory signaling would decrease lung inflammation induced by ventilation in preterm newborn lambs. We also examined if the variability in injury response was explained by variations in the endogenous surfactant pool size.</p> <p>Methods</p> <p>Date-mated preterm lambs (n = 28) were operatively delivered and mechanically ventilated to cause lung injury (tidal volume escalation to 15 mL/kg by 15 min at age). The lambs then were ventilated with 8 mL/kg tidal volume for 1 h 45 min. Groups of animals randomly received specific inhibitors for IL-8, IL-1, or NF-κB. Unventilated lambs (n = 7) were the controls. Bronchoalveolar lavage fluid (BALF) and lung samples were used to quantify inflammation. Saturated phosphatidylcholine (Sat PC) was measured in BALF fluid and the data were stratified based on a level of 5 μmol/kg (~8 mg/kg surfactant).</p> <p>Results</p> <p>The inhibitors did not decrease the cytokine levels or inflammatory response. The inflammation increased as Sat PC pool size in BALF decreased. Ventilated lambs with a Sat PC level > 5 μmol/kg had significantly decreased markers of injury and lung inflammation compared with those lambs with < 5 μmol/kg.</p> <p>Conclusion</p> <p>Lung injury caused by high tidal volumes at birth were decreased when endogenous surfactant pool sizes were larger. Attempts to decrease inflammation by blocking IL-8, IL-1 or NF-κB were unsuccessful.</p

Aging effect on nectar production in two clones of Asclepias syriaca

In common milkweed ( Asclepias syriaca ), flower nectar volumes, concentration and sugar production varied according to the age of the sampled blossoms. In individual blossoms, nectar production peaked daily at 0800 hr. Peak production during the life of the flower occurred on the second day of flowering, 50 h after anthesis, and nectar production ceased after 120 h. The amount and quality of nectar were affected by microclimatic conditions and varied between clones. However, the same secretory patterns were found in all flowers studied. This age dependent nectar secretion combined with the sequential mode of flowering found on a single stem, results in substantial reward for extended periods to nectar feeders.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47744/1/442_2004_Article_BF00378227.pd

Reaction Dynamics at Liquid Interfaces

The liquid interface is a narrow, highly anisotropic region, characterized byrapidly varying density, polarity and molecular structure. We review several aspects ofinterfacial solvation and show how these affect reactivity at liquid/liquid interfaces. Wespecifically consider ion transfer, electron transfer and SN2 reactions, showing thatsolvent effects on these reactions can be understood by considering the unique structureand dynamics of the liquid interface region

Cecília Donnangelo: pioneira na construção teórica de um pensamento social em saúde Cecília Donnangelo: a pioneer in the theoretical construction of social thinking in health

O presente artigo analisa aspectos do percurso intelectual de Maria Cecília Ferro Donnangelo e seus principais trabalhos. Destaca-se no texto o papel inovador e pioneiro da sua obra nos momentos iniciais das ciências sociais no campo da saúde, na segunda metade dos anos 1960, contextualizados no momento em que ocorriam mudanças no ensino médico e na prática da medicina no Brasil.<br>The present article analyzes aspects of the intellectual trajectory of Maria Cecília Ferro Donnangelo and her principal works. The text emphasizes the innovating and pioneer role her work played in the first moments of social sciences in the field of health in the mid sixties, occurring just together with changes in medical education and medical practice in Brazil