Comparison of muscular tissue concentration of heavy metals in Sharpnose stinger (Himantura gerrardi) and Bigeye scade (Selar crumenophthalmus) of the Persian Gulf

We assessed concentration of heavy metals (Cu, Fe, Hg and Zn) in the muscular tissue of benthic species Himantura gerrardi and pelagic species Selar crumenophthalmus caught from the Persian Gulf during winter 2008. After biometrical measurements, the muscle tissues of 51 randomly selected samples were separated from 86 stations. Specimens were digested using the wet method and the concentrations of Cu, Fe and Zn were determined using Atomic Absorption Spectrophotometer (flame method) and also concentration of mercury was determined using Mercury Analyzer device. The mean concentration of heavy metals in muscle tissues of Himantura gerrardi were as follows: Fe: 74.78; Hg: 0.77; Zn: 875.99 and Cu: 3.5. However, these values for muscle tissues of Selar crumenophthalmus were: Fe: 25.07; Hg: 0.20; Cu: Zn: 15.54 and Zn: 2.31kg/g dry weight. Results showed that concentration of the selected heavy metals in H. gerrardi, were significantly higher than Selar crumenophthalmus (P <0.05)

Necrotizing Enterocolitis following Gastroschisis Repair: An Update

Purpose: Necrotizing enterocolitis (NEC) is a known complication of gastroschisis with an incidence above the expected rate in the neonatal population. While many physicians today are aware of this association, the last publication to explore this association in detail and identify possible risk factors of NEC in gastroschisis patients was published over twenty years ago. From our large database of patients with gastroschisis managed by a single group of pediatric surgeons, we reviewed our experience and the recent literature to update what is known about gastroschisis and NEC. Methods: From 2001 to 2017, a gastroschisis registry was maintained. Data from 218 gastroschisis patients were reviewed. Patient demographics and hospital course were reviewed. Patients with confirmed NEC were compared to those without NEC. Results: Two hundred eighteen patients were born with gastroschisis during the time frame of this study. We observed a 5% rate (11 of 218) of NEC. Five patients (45%) developed recurring NEC and 4 patients (36%) were readmitted for NEC development following initial discharge. Variables associated with NEC included low gestational age (P=0.016) and low birth weight (P=0.003). Patients born prior to 37 weeks gestation had a 4.8 times greater risk of developing NEC than those born at term. Rates of IUGR were not statistically different between NEC and non-NEC patients. The method of delivery (cesarean vs vaginal), use of a silo, and form of nutrition were not significantly associated with NEC development. Conclusions: The overall incidence of NEC has decreased compared to earlier reports. NEC does complicate the hospital course for patients, significantly increasing duration of in-hospital treatment. NEC in gastroschisis differs in comparison to traditional NEC, presenting later in life. Risk factors identified include low gestational age and low birth weight. Avoiding elective preterm deliveries may decrease the rate of NEC in gastroschisis

Restoration of myocardial β-adrenergic receptor signaling after left ventricular assist device support

ObjectiveLeft ventricular assist device support for patients with chronic heart failure can significantly improve β-adrenergic receptor signaling, which is likely critical to myocardial recovery. The mechanism underlying the restoration of β-adrenergic receptor signaling is unclear. This study investigates our hypothesis that restoration of cardiac β-adrenergic receptor signaling by left ventricular assist devices results from inhibition of the G protein–coupled receptor kinase-2, a G protein–coupled receptor kinase that specifically phosphorylates and desensitizes agonist-occupied β-adrenergic receptors.MethodsLeft ventricular β-adrenergic receptor signaling was assessed in biopsy specimens taken from patients with chronic heart failure (n = 12) at the time of left ventricular assist device implantation (heart failure group) and again at the time of heart transplantation (left ventricular assist device group). Signaling was also studied in left ventricular biopsy specimens from nonfailing control (n = 8) hearts (nonfailing control group). Signaling was assessed by measuring sarcolemmal membrane β-adrenergic receptor density, adenylyl cyclase activity, G protein expression, and G protein–coupled receptor kinase-2 expression and activity.ResultsLeft ventricular β-adrenergic receptor signaling was severely decreased in the heart failure group versus that seen in the nonfailing control group, as demonstrated by adenylyl cyclase activity. G protein–coupled receptor kinase-2 expression and activity was increased 3-fold in the heart failure group versus that seen in the nonfailing control group. After left ventricular assist device support, β-adrenergic receptor signaling was restored to levels similar to those seen in the nonfailing control group. G protein–coupled receptor kinase-2 expression and activity were markedly diminished after left ventricular assist device support compared with that seen in the heart failure group and were not different from that seen in the nonfailing control group.ConclusionIn chronic heart failure left ventricular assist device support leads to restoration of cardiac β-adrenergic receptor signaling. The primary mechanism appears to be diminished myocardial G protein–coupled receptor kinase-2 activity. This demonstrates the potentially beneficial effects of G protein–coupled receptor kinase-2 inhibition on β-adrenergic receptor signaling in heart failure and might represent a novel therapeutic strategy for this disease process

Development of polychormatic irregular waves for testing OWC bidirectional turbines at a land-based test facility

This paper presents the development of a control strategy that allows a dedicated oscillating water column turbine test facility to produce polychromatic waves. This facility allows testing of bi-directional turbines under transient conditions, validation of computational fluid dynamics simulations and testing of turbine control strategies under realistic sea states. The test facility employs a pneumatic wave generator (of unique design) to simulate the air flow of an oscillating water column. This work describes the methodology to create wave time series of various spectra that replicate a range of wave states at various geographical locations employing this rig

Gastric outlet obstruction due to adenocarcinoma in a patient with Ataxia-Telangiectasia syndrome: a case report and review of the literature

Background: Ataxia-Telangiectasia syndrome is characterized by progressive cerebellar dysfunction, conjuctival and cutaneous telangiectasias, severe immune deficiencies, premature aging and predisposition to cancer. Clinical and radiographic evaluation for malignancy in ataxia-telangiectasia patients is usually atypical, leading to delays in diagnosis. Case presentation: We report the case of a 20 year old ataxia-telangiectasia patient with gastric adenocarcinoma that presented as complete gastric outlet obstruction. Conclusion: A literature search of adenocarcinoma associated with ataxia-telangiectasia revealed 6 cases. All patients presented with non-specific gastrointestinal complaints suggestive of ulcer disease. Although there was no correlation between immunoglobulin levels and development of gastric adenocarcinoma, the presence of chronic gastritis and intestinal metaplasia seem to lead to the development of gastric adenocarcinoma. One should consider adenocarcinoma in any patient with ataxia-telangiectasia who presents with non-specific gastrointestinal complaints, since this can lead to earlier diagnosis

Characterising the nicotine metabolite ratio and its association with treatment choice: A cross sectional analysis of Stop Smoking Services in England

Pharmacotherapy provision based on Nicotine Metabolite Ratio (NMR) status (slow/normal metabolism) may improve smoking cessation rates. However, it is unclear whether NMR status is consistent across patient characteristics and current treatment choice. Data come from 1,826 participants attending Stop Smoking Services (SSS) across England in 2012/13. Sociodemographic, mental/physical health, smoking and treatment characteristics (nicotine replacement therapy vs. other pharmacotherapy; group vs. one-to-one behavioural support) were assessed. Salivary nicotine metabolites were measured and NMR (3-hydroxycotinine/cotinine) computed, characterising smokers as slow (NMR < 0.31) or normal (NMR ≥ 0.31) metabolisers. Normal metabolisers were older than slow metabolisers (Odds Ratio (OR) = 1.49, 95% Confidence Interval (CI) = 1.32-1.69) but no other characteristics were associated with NMR status. Overall, predictors accounted for only 7.3% of NMR variance. In adjusted analysis, pharmacotherapy type was not associated with NMR status, but normal metabolisers were less likely to use group support (OR = 0.67, 95% CI = 0.51-0.89). NMR status does not vary substantially across sociodemographic characteristics. Given its impact on pharmacotherapy efficacy, the lack of an association with pharmacotherapy choice suggests there is scope to use NMR status to optimise the selection and efficacy of smoking cessation pharmacotherapy. The unexpected association of NMR status with behavioural support should be explored further

Mechanisms of airfoil noise near stall conditions

The focus of this paper is on investigating the noise produced by an airfoil at high angles of attack over a range of Reynolds number Re≈2×10⁵–4×10⁵. The objective is not modeling this source of noise but rather understanding the mechanisms of generation for surface pressure fluctuations, due to a separated boundary layer, that are then scattered by the trailing edge. To this aim, we use simultaneous noise and surface pressure measurement in addition to velocimetric measurements by means of hot wire anemometry and time-resolved particle image velocimetry. Three possible mechanisms for the so-called “separation-stall noise” have been identified in addition to a clear link between far-field noise, surface pressure, and velocity fields in the noise generation

Progress Toward Future Runway Management

The runway is universally acknowledged as a constraining factor to capacity in the National Airspace System (NAS). It follows that investigation of the effective use of runways, both in terms of selection and assignment, is paramount to the efficiency of future NAS operations. The need to address runway management is not a new idea; however, as the complexities of factors affecting runway selection and usage increase, the need for effective research in this area correspondingly increases. Under the National Aeronautics and Space Administration s Airspace Systems Program, runway management is a key research area. To address a future NAS which promises to be a complex landscape of factors and competing interests among users and operators, effective runway management strategies and capabilities are required. This effort has evolved from an assessment of current practices, an understanding of research activities addressing surface and airspace operations, traffic flow management enhancements, among others. This work has yielded significant progress. Systems analysis work indicates that the value of System Oriented Runway Management tools is significantly increased in the metroplex environment over that of the single airport case. Algorithms have been developed to provide runway configuration recommendations for a single airport with multiple runways. A benefits analysis has been conducted that indicates the SORM benefits include supporting traffic growth, cost reduction as a result of system efficiency, NAS optimization from metroplex operations, fairness in aircraft operations, and rational decision making