Palm tree mulch as substrate for primary treatment wetlands processing high strength urban wastewater.

The life span of subsurface flow treatment wetlands is determined by the clogging of the substrate. Thus, the influent should undergo primary treatment to reduce loadings of suspended solids and dissolved organic matter. An-organic based substrate should be less prone to clogging because of its remarkably higher porosity and plasticity. Mulch obtained from branches of the Canarian palm tree (Phoenix canariensis) has been tested as substrate for mixed flow, intermittently fed treatment wetland mesocosms processing high strength urban wastewater. The effect of the presence of plants (Phragmites and Cyperus), influent pressure and hydraulic loading rate was studied. The best removals (SS: 89%, COD: 77%, turbidity: 82%) have been obtained with planted reactors treating highly concentrated influents at the lower hydraulic loading rates tested. The palm tree mulch units achieved similar removals of SS, COD and turbidity to one having gravel as substrate and planted with common reed. Mulch obtained from stems of giant reed (Arundo donax) provided similar removals of SS and turbidity but that of COD was lower. The combination of organic-based TWs with gravel-based ones provided high removals (SS: 95%, COD: 78%, turbidity: 95%) while the risk of clogging was strongly reduced.

Estrogen receptors in human pituitary tumors.

The relationship between the presence of estrogen receptors in pituitary adenomas and the post surgical evolution of the patients in order to find another prognostic parameter for these tumors have been studied to improve the treatment selection. Estrogen receptors were studied by immunocytochemistry in histological sections of paraffin embedded 42 pituitary adenomas. Only 19% of these tumors were positive for estrogen receptors. As expected, the higher concentration (60%) was found in prolactin secreting adenomas, although we found estrogen receptors in one somatotroph and in one nonsecreting. The most aggressive tumors were those negative for estrogen receptors within the prolactinomas and the positive somatotrophinoma. The results of this work suggest that the determination of estrogen receptors in pituitary tumors might help as a prognostic factor in these adenomas.

The multiple facets of Per2.

The Period 2 (Per2) gene is an important component of the circadian system. It appears to be not only part of the core oscillator mechanism, but also part of the input and output pathways of the clock. Because of its involvement at multiple levels of the circadian system, Per2 needs to meet a variety of different demands. We discuss how Per2 might be able to fulfill multiple functions by reviewing known facts and combine this with speculations based on these facts. This might provide new views about Per2 function and help to better understand diseases that are rooted in the circadian system.

An evaluation of extubation failure predictors in mechanically ventilated infants and children.

OBJECTIVE: To assess the accuracy of traditional weaning indices in predicting extubation failure, and to compare their accuracy when indices are measured at the onset of a breathing trial (SBT) and at the end of the SBT before extubation. DESIGN: Prospective study. SETTING: Medical-surgical intensive care unit at a tertiary care hospital. PATIENTS: Four hundred eighteen consecutive infants and children who received mechanical ventilation for at least 48 h and were deemed ready to undergo a SBT by their primary physician. INTERVENTIONS: Respiratory frequency (RR), tidal volume (V(T)), maximal inspiratory pressure (P(imax)) and frequency-to-tidal volume ratio (f/V(T)) were obtained within the first 5 min of breathing through a T-piece. The primary physicians were unaware of those measurements and the decision to extubate a patient was made by them. RR, V(T), f/V(T) were remeasured before extubation by the respiratory therapists. Extubation failure was defined as needing re intubation within 48 h after extubation. The area under the receiver operating characteristic (ROC) curve was calculated for each index as a measure of the accuracy in predicting extubation outcome. MEASUREMENTS AND MAIN RESULTS: Three hundred twenty-three patients successfully underwent the SBT and were extubated, but 48 of them (14%) required re-intubation. The ROC curve for V(T), RR, P(imax) and f/V(T) measured within the first 5 min of breathing were 0.54, 0.56, 0.57 and 0.57, respectively. The ROC curve did not increase significantly when the above indices were remeasured before extubation. CONCLUSIONS: In a population which had passed SBT, the ability of the traditional weaning indices to discriminate between children successfully extubated and children re-intubated is very poor.

Tonometry in pediatric patients: a comparative study among Tono-pen, Perkins, and Schiötz tonometers.

Measuring the intraocular pressure (IOP) in children can be difficult. We compared the accuracy of IOP measurements in pediatric patients using three tonometers: Perkins, Schiötz, and Tono-pen. Seventy-seven children (132 eyes; average age, 1 year, 7 months; range, 1 month to 60 months), mainly afflicted with retinopathy of prematurity (107 eyes), were evaluated. A good correlation (r = 0.867) was found between the Tono-pen and the Perkins tonometers. No statistical difference was found between the mean difference of IOP values obtained with the Tono-pen and the Perkins (P > .05). The Schiötz measurements were significantly higher than those obtained with the Perkins and the Tono-pen tonometers (P < .05). We concluded that the Tono-pen tonometer has a higher correlation coefficient, comparable to the Perkins tonometer, and can be used reliably to assess IOP in pediatric patients.