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BackgroundImpaired alveolar fluid clearance, determined in part by alveolar sodium transport, is associated with acute respiratory distress syndrome (ARDS). Nasal sodium transport may reflect alveolar transport. The primary objective of this prospective, observational study was to determine if reduced nasal sodium transport, as measured by nasal potential difference (NPD), was predictive of the development of and outcome from ARDS.MethodsNPD was measured in 15 healthy controls and in 88 patients: 40 mechanically ventilated patients defined as ‘at-risk’ for ARDS, 61 mechanically ventilated patients with ARDS (13 who were previously included in the ‘at-risk’ group) and 8 ARDS survivors on the ward.ResultsIn at-risk subjects, maximum NPD (mNPD) was greater in those who developed ARDS (difference –8.4 mV; 95% CI –13.8 to –3.7; p=0.005) and increased mNPD predicted the development of ARDS before its onset (area under the curve (AUC) 0.75; 95% CI 0.59 to 0.89). In the ARDS group, mNPD was not significantly different for survivors and non-survivors (p=0.076), and mNPD was a modest predictor of death (AUC 0.60; 95% CI 0.45 to 0.75). mNPD was greater in subjects with ARDS (−30.8 mV) than in at-risk subjects (−24.2 mV) and controls (−19.9 mV) (pConclusionsIncreased NPD predicts the development of ARDS in at-risk subjects but does not predict mortality. NPD increases before ARDS develops, is greater during ARDS, but is not significantly different for controls and survivors. These results may reflect the upregulated sodium transport necessary for alveolar fluid clearance in ARDS. NPD may be useful as a biomarker of endogenous mechanisms to stimulate sodium transport. Larger studies are now needed to confirm these associations and predictive performance.

Individuals with cystic fibrosis (CF) experience frequent acute pulmonary exacerbations, which lead to decreased lung function and reduced quality of life.The goal of this study was to determine if an intervention directed toward early detection of pulmonary exacerbations using home spirometry and symptom monitoring would result in slower decline in lung function than in control subjects.We conducted a multicenter, randomized trial at 14 CF centers with subjects at least 14 years old. The early intervention arm subjects measured home spirometry and symptoms electronically twice per week. Sites were notified if a participant met criteria for an exacerbation and contacted participants to determine if treatment for acute exacerbation was required. Participants in the usual care arm were seen every 3 months and were asked to contact the site if they were concerned about worsening pulmonary symptoms.The primary outcome was the 52-week change in FEVAn intervention of home monitoring among patients with CF was able to detect more exacerbations than usual care, but this did not result in slower decline in lung function. Clinical trial registered with www.clinicaltrials.gov (NCT01104402).

Minimization is an alternative method to stratified permuted block randomization, which may be more effective at balancing treatments when there are many strata. However, its use in the regulatory setting for industry trials remains controversial, primarily due to the difficulty in interpreting conventional asymptotic statistical tests under restricted methods of treatment allocation. We argue that the use of minimization should be critically evaluated when designing the study for which it is proposed. We demonstrate by example how simulation can be used to investigate whether minimization improves treatment balance compared with stratified randomization, and how much randomness can be incorporated into the minimization before any balance advantage is no longer retained. We also illustrate by example how the performance of the traditional model-based analysis can be assessed, by comparing the nominal test size with the observed test size over a large number of simulations. We recommend that the assignment probability for the minimization be selected using such simulations.

Objective: To describe the burden of bilateral neovascular age-related macular degeneration (NV-AMD) on patient-reported functioning and health resource utilization. Methods: A cross-sectional study of 401 patients with bilateral NV-AMD and 471 elderly control subjects without AMD was conducted in 5 countries. Subjects completed a telephone survey, including the National Eye Institute 25-Item Visual Function Questionnaire, the EuroQol instrument, the Hospital Anxiety and Depression Scale, and history of falls, fractures, and health care resource utilization. Results: The mean age for patients with NV-AMD was 78.1 years, and 65% were women. The patients reported 45% worse vision-related functioning, 13% worse overall wellbeing, and 30% more anxiety and 42% more depression symptoms than controls after adjusting for covariates (all, P

Policy towards speculative bubbles is examined in a model of a finite horizon 'greater fool' bubble, with rational agents, asymmetric information and short-sales constraints. This model permits the use of standard tools of comparative dynamics and welfare economics to analyze bubble policies. Government policy is modeled as deflating overpriced assets by revealing information about whether or not the asset is overpriced. It is shown that such a policy tends to improve welfare if it protects less-informed buyers from 'bad' sellers, who know the asset is overpriced. However, if policy deflates prices only in 'strong bubbles,', where all private agents know the asset is overpriced, this tends to reduce welfare. This is because, in those states where the central bank turns out not to deflate prices, bad sellers become more confident of selling the asset. That is, bubble bursting protects bad sellers from each other, which, in turn, can exacerbate the lemons problem in states where the asset is valuable.

Human monocytes have been shown to be critical immunoregulatory cells for a variety of frequently measured in vitro human immune functions and are secretors of potent biologic response modifiers (BRMs). These BRMs, such as interferon (IFN), colony stimulating factor (CSF) and prostaglandin E (PGE), may play important roles in the host immune response to cancer. A new approach for culturing circulating peripheral blood monocytes has been developed to retain the native characteristics of these cells, avoiding possible alteration or activation by adherence. The ability of elutriator-purified human monocytes to secrete IFN and PGE was examined under conditions of suspension culture as well as after adherence, and no difference in secretion of these BRMs was noted. In contrast, Teflon-cultured monocytes demonstrated a significantly enhanced CSF release over culturing in polystyrene plates. A new serum-free medium has also been developed, and monocytes cultured in vitro in this medium showed a 5-fold increase in IFN release, and up to a 72% increase in CSF release when compared to optimal standard culture medium (containing 10% AB serum) and an increased stimulation index for PGE release. By these procedures, hundreds of millions of highly purified human monocytes can be sterilely isolated in suspension and cultured in suspension in serum-free medium with retention of BRM-releasing capabilities. This system should permit more detailed molecular studies of monocytes (in which serum can be an impediment) and may also facilitate clinical therapy studies involving the in vivo transfer of monocytes activated in suspension in vitro.

134 patients with a variety of malignancies were treated in two Phase 1 clinical trials of recombinant leukocyte A interferon (IFN) produced by recombinant DNA methodology by Hoffmann-La Roche Inc. in collaboration with Genentech Inc. IFN was given either twice daily or three times weekly for 28 days. Extensive monitoring of immune function was done on these patients, in an attempt to define the range of doses of interferon and timing of administration that would optimally alter immune functions which might have beneficial anti-tumor effects. These two protocols failed to result in an appreciable increase in NK activity but rather in the majority of patients there was no significant change in NK activity from the pretreatment baseline levels. A particularly unexpected finding was the depresssion in NK activity seen in 30% of the patients. In contrast, the IFN preparation did induce significant augmentation of monocyte function, as measured in a monocyte-mediated cytostatic assay, with increases observed in 80% of the patients. There is some evidence for the presence of a suppressor factor in the sera of these patients which interfered with in vitro boosting of NK activity by IFN and therefore might have been responsible for the paradoxical NK results. These data have also been analyzed in terms of their possible relationship to doses, and protocol of IFN administration, and to tumor response.