Activation and modulation of recombinant glycine and GABAA receptors by 4-halogenated analogues of propofol

BACKGROUND AND PURPOSE: Glycine receptors are important players in pain perception and movement disorders, and therefore an important therapeutic target. Glycine receptors can be modulated by the intravenous anesthetic propofol (2,6-diisopropylphenol); however, the drug is more potent, by at least one order of magnitude, on GABAA receptors. It has been proposed that halogenation of the propofol molecule generates compounds with selective enhancement of glycinergic modulatory properties. EXPERIMENTAL APPROACH: We synthesized 4-bromopropofol, 4-chloropropofol, and 4-fluoropropofol. The direct activating and modulatory effects of these drugs and propofol were compared on recombinant rat glycine and human GABAA receptors expressed in oocytes. Behavioral effects of the compounds were compared in the tadpole loss-of-righting assay. KEY RESULTS: The concentration-response curves for potentiation of homomeric α1, α2, and α3 glycine receptors were shifted to lower drug concentrations by 2-10-fold for the halogenated compounds. Direct activation by all compounds was minimal with all subtypes of the glycine receptor. The four compounds were essentially equally potent modulators of the α1β3γ2L GABAA receptor with EC50 s between 4 and 7 μM. The EC50 s for loss-of-righting in Xenopus tadpoles, a proxy for loss of consciousness and considered to be mediated by actions on GABAA receptors, ranged from 0.35 to 0.87 μM. Conclusions and Implications We confirm that halogenation of propofol more strongly affects modulation of homomeric glycine receptors than α1β3γ2L GABAA receptors. However, the effective concentrations of all tested halogenated compounds remained lower for GABAA receptors. We infer that 4-bromo-, 4-chloro, or 4-fluoropropofol are not selective homomeric glycine receptor modulators

Rapid detection of pandemic influenza in the presence of seasonal influenza

Background: Key to the control of pandemic influenza are surveillance systems that raise alarms rapidly and sensitively. In addition, they must minimise false alarms during a normal influenza season. We develop a method that uses historical syndromic influenza data from the existing surveillance system 'SERVIS' (Scottish Enhanced Respiratory Virus Infection Surveillance) for influenza-like illness (ILI) in Scotland. Methods: We develop an algorithm based on the weekly case ratio (WCR) of reported ILI cases to generate an alarm for pandemic influenza. From the seasonal influenza data from 13 Scottish health boards, we estimate the joint probability distribution of the country-level WCR and the number of health boards showing synchronous increases in reported influenza cases over the previous week. Pandemic cases are sampled with various case reporting rates from simulated pandemic influenza infections and overlaid with seasonal SERVIS data from 2001 to 2007. Using this combined time series we test our method for speed of detection, sensitivity and specificity. Also, the 2008-09 SERVIS ILI cases are used for testing detection performances of the three methods with a real pandemic data. Results: We compare our method, based on our simulation study, to the moving-average Cumulative Sums (Mov-Avg Cusum) and ILI rate threshold methods and find it to be more sensitive and rapid. For 1% case reporting and detection specificity of 95%, our method is 100% sensitive and has median detection time (MDT) of 4 weeks while the Mov-Avg Cusum and ILI rate threshold methods are, respectively, 97% and 100% sensitive with MDT of 5 weeks. At 99% specificity, our method remains 100% sensitive with MDT of 5 weeks. Although the threshold method maintains its sensitivity of 100% with MDT of 5 weeks, sensitivity of Mov-Avg Cusum declines to 92% with increased MDT of 6 weeks. For a two-fold decrease in the case reporting rate (0.5%) and 99% specificity, the WCR and threshold methods, respectively, have MDT of 5 and 6 weeks with both having sensitivity close to 100% while the Mov-Avg Cusum method can only manage sensitivity of 77% with MDT of 6 weeks. However, the WCR and Mov-Avg Cusum methods outperform the ILI threshold method by 1 week in retrospective detection of the 2009 pandemic in Scotland. Conclusions: While computationally and statistically simple to implement, the WCR algorithm is capable of raising alarms, rapidly and sensitively, for influenza pandemics against a background of seasonal influenza. Although the algorithm was developed using the SERVIS data, it has the capacity to be used at other geographic scales and for different disease systems where buying some early extra time is critical

Extragalactic Radio Continuum Surveys and the Transformation of Radio Astronomy

Next-generation radio surveys are about to transform radio astronomy by discovering and studying tens of millions of previously unknown radio sources. These surveys will provide new insights to understand the evolution of galaxies, measuring the evolution of the cosmic star formation rate, and rivalling traditional techniques in the measurement of fundamental cosmological parameters. By observing a new volume of observational parameter space, they are also likely to discover unexpected new phenomena. This review traces the evolution of extragalactic radio continuum surveys from the earliest days of radio astronomy to the present, and identifies the challenges that must be overcome to achieve this transformational change.Comment: To be published in Nature Astronomy 18 Sept 201

Colorectal cancer health services research study protocol: the CCR-CARESS observational prospective cohort project

BACKGROUND: Colorectal cancers are one of the most common forms of malignancy worldwide. But two significant areas of research less studied deserve attention: health services use and development of patient stratification risk tools for these patients. METHODS:DESIGN: a prospective multicenter cohort study with a follow up period of up to 5 years after surgical intervention. Participant centers: 22 hospitals representing six autonomous communities of Spain. Participants/Study population: Patients diagnosed with colorectal cancer that have undergone surgical intervention and have consented to participate in the study between June 2010 and December 2012. Variables collected include pre-intervention background, sociodemographic parameters, hospital admission records, biological and clinical parameters, treatment information, and outcomes up to 5 years after surgical intervention. Patients completed the following questionnaires prior to surgery and in the follow up period: EuroQol-5D, EORTC QLQ-C30 (The European Organization for Research and Treatment of Cancer quality of life questionnaire) and QLQ-CR29 (module for colorectal cancer), the Duke Functional Social Support Questionnaire, the Hospital Anxiety and Depression Scale, and the Barthel Index. The main endpoints of the study are mortality, tumor recurrence, major complications, readmissions, and changes in health-related quality of life at 30 days and at 1, 2, 3 and 5 years after surgical intervention. STATISTICAL ANALYSIS: In relation to the different endpoints, predictive models will be used by means of multivariate logistic models, Cox or linear mixed-effects regression models. Simulation models for the prediction of discrete events in the long term will also be used, and an economic evaluation of different treatment strategies will be performed through the use of generalized linear models. DISCUSSION: The identification of potential risk factors for adverse events may help clinicians in the clinical decision making process. Also, the follow up by 5 years of this large cohort of patients may provide useful information to answer different health services research questions

A propofol binding site on mammalian GABAA receptors identified by photolabeling

Propofol is the most important intravenous general anesthetic in current clinical use. It acts by potentiating GABA(A) receptors, but where it binds to this receptor is not known and has been a matter of some controversy. We have synthesized a novel propofol analogue photolabeling reagent that has a biological activity very similar to that of propofol. We confirmed that this reagent labeled known propofol binding sites in human serum albumin which have been identified using X-ray crystallography. Using a combination of the protiated label and a deuterated version, and mammalian receptors labeled in intact membranes, we have identified a novel binding site for propofol in GABA(A) receptors consisting of both β(3) homopentamers and α(1)β(3) heteropentamers. The binding site is located within the β subunit, at the interface between the transmembrane domains and the extracellular domain, and lies close to known determinants of anesthetic sensitivity in transmembrane segments TM1 and TM2

Quantitative X-ray Tomography of the Mouse Cochlea

Imaging with hard X-rays allows visualizing cochlear structures while maintaining intrinsic qualities of the tissue, including structure and size. With coherent X-rays, soft tissues, including membranes, can be imaged as well as cells making use of the so-called in-line phase contrast. In the present experiments, partially coherent synchrotron radiation has been used for micro-tomography. Three-dimensional reconstructions of the mouse cochlea have been created using the EM3D software and the volume has been segmented in the Amira Software Suite. The structures that have been reconstructed include scala tympani, scala media, scala vestibuli, Reissner's membrane, basilar membrane, tectorial membrane, organ of Corti, spiral limbus, spiral ganglion and cochlear nerve. Cross-sectional areas of the scalae were measured. The results provide a realistic and quantitative reconstruction of the cochlea

Population distribution and burden of acute gastrointestinal illness in British Columbia, Canada

BACKGROUND: In developed countries, gastrointestinal illness (GI) is typically mild and self-limiting, however, it has considerable economic impact due to high morbidity. METHODS: The magnitude and distribution of acute GI in British Columbia (BC), Canada was evaluated via a cross-sectional telephone survey of 4,612 randomly selected residents, conducted from June 2002 to June 2003. Respondents were asked if they had experienced vomiting or diarrhoea in the 28 days prior to the interview. RESULTS: A response rate of 44.3% was achieved. A monthly prevalence of 9.2% (95%CI 8.4 – 10.0), an incidence rate of 1.3 (95% CI 1.1–1.4) episodes of acute GI per person-year, and an average probability that an individual developed illness in the year of 71.6% (95% CI 68.0–74.8), weighted by population size were observed. The average duration of illness was 3.7 days, translating into 19.2 million days annually of acute GI in BC. CONCLUSION: The results corroborate those from previous Canadian and international studies, highlighting the substantial burden of acute GI

Effects of NFKB1 and NFKBIA Gene Polymorphisms on Susceptibility to Environmental Factors and the Clinicopathologic Development of Oral Cancer

encoding IkappaBalpha (IκBα) with both the susceptibility to develop OSCC and the clinicopathological characteristics of the tumors.<.05), compared with those patients CC homozygotes. 519 might be a predictive factor for the distal metastasis of OSCC in Taiwanese

Retention of progenitor cell phenotype in otospheres from guinea pig and mouse cochlea

Abstract\ud \ud Background\ud Culturing otospheres from dissociated organ of Corti is an appropriate starting point aiming at the development of cell therapy for hair cell loss. Although guinea pigs have been widely used as an excellent experimental model for studying the biology of the inner ear, the mouse cochlea has been more suitable for yielding otospheres in vitro. The aim of this study was to compare conditions and outcomes of otosphere suspension cultures from dissociated organ of Corti of either mouse or guinea pig at postnatal day three (P3), and to evaluate the guinea pig as a potential cochlea donor for preclinical cell therapy.\ud \ud \ud Methods\ud Organs of Corti were surgically isolated from P3 guinea pig or mouse cochlea, dissociated and cultivated under non-adherent conditions. Cultures were maintained in serum-free DMEM:F12 medium, supplemented with epidermal growth factor (EGF) plus either basic fibroblast growth factor (bFGF) or transforming growth factor alpha (TGFα). Immunofluorescence assays were conducted for phenotype characterization.\ud \ud \ud Results\ud The TGFα group presented a number of spheres significantly higher than the bFGF group. Although mouse cultures yielded more cells per sphere than guinea pig cultures, sox2 and nestin distributed similarly in otosphere cells from both organisms. We present evidence that otospheres retain properties of inner ear progenitor cells such as self-renewal, proliferation, and differentiation into hair cells or supporting cells.\ud \ud \ud Conclusions\ud Dissociated guinea pig cochlea produced otospheres in vitro, expressing sox2 and nestin similarly to mouse otospheres. Our data is supporting evidence for the presence of inner ear progenitor cells in the postnatal guinea pig. However, there is limited viability for these cells in neonatal guinea pig cochlea when compared to the differentiation potential observed for the mouse organ of Corti at the same developmental stage

Guideline adherence for early breast cancer before and after introduction of the sentinel node biopsy

This population-based study aimed to analyse variations in surgical treatment and guideline compliance with respect to the application of radiotherapy and axillary lymph node dissection (ALND), for early breast cancer, before and after the sentinel node biopsy (SNB) introduction. The study included 13 532 consecutive surgically treated stage I–IIIA breast cancer patients diagnosed in 1989–2002. Hospitals showed large variation in breast-conserving surgery (BCS) rates, ranging between 27 and 72% for T1 and 14 and 42% for T2 tumours. In multivariate analysis marked inter-hospital and time-dependent variation in the BCS rate remained after correction for case-mix. The guideline adherence was markedly lower for elderly patients. In 25.2% of the patients aged ⩾75 years either ALND or radiotherapy were omitted. The proportion of patients with no ALND after an SNB increased from 1.8% in 1999 to 37.8% in 2002. However, in 2002 also 12.2% of the patients with a positive SNB did not have an ALND. Guideline compliance for BCS, with respect to radiotherapy and ALND, fell since the SNB introduction, from 96.1% before 2000 to 91.4% in 2002 (P<0.001). Noncompliance may however reflect patient-tailored medicine, as for elderly patients with small, radically resected primary tumours. The considerable variation in BCS-rates is more consistent with variations in surgeon preferences than patient's choice