During fetal life, the future airways of the lung are filled with a liquid that plays a crucial role in the growth and development of the lungs by maintaining them in an expanded state. Lung liquid is secreted across the pulmonary epithelium into the lung lumen due to the osmotic gradient established by the net movement of Cl _ in the same direction. It is not known exactly when lung liquid secretion begins, but fluid is present by midgestation in fetal sheep and is secreted at 2-4 ml kg _1 h _1 between 120 days of gestation and term (~150 days). Fetal lung liquid exits the lungs via the trachea, whereby it is either swallowed (approximately 50 %) or passes directly into the amniotic sac, where it contributes to amniotic fluid volume (Harding & Hooper, 1999).If the fetal trachea is obstructed, which prevents the outward flow of lung liquid, the fetal lung expands with accumulated liquid. This is a potent stimulus for fetal lung growth and also greatly reduces the proportion of type-II alveolar epithelial cells (AECs). Lung liquid drainage on the other hand, deflates the lung, causes lung growth to cease, but increases the proportion of type-II AECs, possibly via type-I to type-II cell differentiation (Flecknoe et al. 2002). As a result it is now widely recognized that the degree to which the fetal lungs are expanded by lung liquid determines the growth and structural development of the lung, as well as the differentiated state of type-I and type-II AECs (Harding & Hooper, 1999). Despite the importance of lung liquid in the development of the lung, the factors controlling the movement of liquid across the pulmonary epithelium have not been fully explored. Furthermore, the effective clearance of lung liquid at birth is vital to allow the entry of air into the lungs with the onset of respiratory gas exchange. This process is largely dependent on the capability of the epithelium to reabsorb large quantities of water.Aquaporins (AQPs) are specific water channels that allow the rapid transcellular movement of water in response to osmotic/hydrostatic pressure gradients (King & Yasui, 2002). At least four AQPs (AQP1, 3, 4 and 5) are expressed in the lungs of various species, including humans, rats, mice and rabbits, although some discrepancies exist in the specific sites of distribution of these proteins. In all species described so far (human, rat, mouse), AQP1 is expressed in the apical and basolateral membrane of the microvascular endothelium and decreased pulmonary vascular permeability has been shown in AQP1-null humans . AQP3 is expressed in the basolateral membrane of basal cells of the tracheal epithelium and in submucosal gland cell membranes in rodents, but is also found in bronchioles (apical membrane) and type-II alveolar Fetal lung development is dependent upon secretion of liquid into the future airways which must be cleared at birth to establish air-breathing. Aquaporins (AQP) 1, 3, 4 and 5 are membranous water channel proteins that are present in the lung after birth in rodents, with little expression be...

Background:Laparoscopic radical cystectomy (LRC) is increasingly being used for muscle-invasive bladder cancer. However, high levels of clinical evidence comparing laparoscopic vs open radical cystectomy (ORC) are lacking.Methods:A prospective randomised controlled clinical trial comparing LRC vs ORC in patients undergoing radical cystectomy for bladder cancer. Thirty-five patients were eligible for final analysis in each group.Results:The median follow-up was 26 months (range, 4–59 months) for laparoscopic vs 32 months (range, 6–60 months) for ORC. Significant differences were noted in operative time, estimated blood loss (EBL), blood transfusion rate, analgesic requirement, and time to resumption of oral intake. No significant differences were noted in the length of hospital stay, complication rate, lymph node yield (14.1±6.3 for LRC and 15.2±5.9 for ORC), positive surgical margin rate, postoperative pathology, or recurrence rate (7 for LRC and 8 for ORC). The 5-year recurrence-free survival with laparoscopic vs ORC was 78.5% vs 70.9%, respectively (P=0.773). The overall survival with laparoscopic vs ORC was 73.8% vs 67.4%, respectively (P=0.511).Conclusion:Our study demonstrated that LRC is superior to ORC in perioperative outcomes, including EBL, blood transfusion rate, and analgesic requirement. We found no major difference in oncologic outcomes. The number of patients is too small to allow for a final conclusion.

A relatively high rate of fungal endophthalmitis suggests that sterilization patterns in local hospitals should be further revised. A delayed presentation, inappropriate treatment procedures, poor presenting VA, and causative organism virulence may account for the unfavorable visual outcome in this study.

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