Spatiotemporal Calibration of Atmospheric Nitrogen Dioxide Concentration Estimates From an Air Quality Model for Connecticut

A spatiotemporal calibration and resolution refinement model was fitted to calibrate nitrogen dioxide (NO$_2$) concentration estimates from the Community Multiscale Air Quality (CMAQ) model, using two sources of observed data on NO$_2$ that differed in their spatial and temporal resolutions. To refine the spatial resolution of the CMAQ model estimates, we leveraged information using additional local covariates including total traffic volume within 2 km, population density, elevation, and land use characteristics. Predictions from this model greatly improved the bias in the CMAQ estimates, as observed by the much lower mean squared error (MSE) at the NO$_2$ monitor sites. The final model was used to predict the daily concentration of ambient NO$_2$ over the entire state of Connecticut on a grid with pixels of size 300 x 300 m. A comparison of the prediction map with a similar map for the CMAQ estimates showed marked improvement in the spatial resolution. The effect of local covariates was evident in the finer spatial resolution map, where the contribution of traffic on major highways to ambient NO$_2$ concentration stands out. An animation was also provided to show the change in the concentration of ambient NO$_2$ over space and time for 1994 and 1995.Comment: 23 pages, 8 figures, supplementary materia

Synthesis, structural and antibacterial study of new silver complex with 3-acetyl-2H chromene-2-one

A new silver complex [Ag(C11H8O3)2]NO3 was synthesized by the reaction of silver nitrateand coumarin based ligand (3-acetyl-2H-chromene-2-one) through solution method. The product was characterized using different analytical techniques like melting point, Infrared spectroscopy, Raman spectroscopy, powder X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, atomic absorption spectroscopy and mass spectrometry. An antibacterial study of the complex was also studied for its possible use in medical treatment. KEY WORDS: Silver complex, Acetyl coumarin, Vibrational analysis, Antibacterial study Bull. Chem. Soc. Ethiop. 2016, 30(3), 403-411DOI: http://dx.doi.org/10.4314/bcse.v30i3.

Effects of lipoproteins on cyclo-oxygenase and lipoxygenase pathways in human platelets

The products of arachidonic acid (AA) metabolism in platelets play an important role in platelet shape change, adhesion and aggregation which may participate in the pathogenesis of ischemic heart disease and thrombosis. Since lipoproteins are also involved in the pathogenesis of thrombo-embolic disorders, the effect of human lipoproteins (HDL, LDL, VLDL) on AA metabolism in human platelets was investigated. Lipoproteins were separated by density gradient zonal ultracentrifugation. The effects of lipoproteins on production of AA metabolites in human platelets i.e., thromboxane A2 (TXA2) and hydroxy-eicosatetraenoic acids (HETEs) were examined using radiometric thin layer chromatography coupled with automated data integrator system. In human platelets, HDL inhibited 12-HETE and TXA2 formation in a concentration-dependent manner. LDL had a strong inhibitory effect on TXA2 production and a weak inhibitory effect on 12-HETE production. VLDL had no effect on platelet AA metabolism. These findings point to a new facet of lipoproteins action and suggest that lipoproteins may have a physiological role in the regulation of AA metabolism in platelets

Effect of pioglitazone therapy on high sensitive C-reactive protein and lipid profile in diabetic patients with renal transplantation; a randomize clinical trial

Background: Inflammation has a major role in disease lead to renal failure and diabetes mellitus, controlling inflammation in diabetic kidney receivers could decrease morbidity and mortality. Objectives: This study designed for evaluating the efficacy of pioglitazone on C-reactive protein and lipid profile in diabetic kidney transplant receivers. Patients and Methods: In this double blinded clinical trial, 58 diabetic renal transplant receivers, in first month after transplantation, randomized into two groups; receiving insulin and pioglitazone (15 mg tablet daily, group A); and insulin and placebo (group B). Blood pressure, weight, body mass index (BMI) and laboratory data compared in before and after 4-month treatment in two groups by SPSS. Results: Fifty-eight patients with mean age of 44.15 ± 2 years included. There were no significant difference between groups in demographic data and other baseline measured variables (P > 0.05).The mean weigh and BMI were slightly increased in group A and decreased in group B. The mean hs-CRP was decreased 4.82 mg/dL in group A and 1.93 mg/dL in group B (P = 0.007). The mean total serum cholesterol was significantly decreased 34 mg/dL in group A and 18.07 mg/dL in group B (P = 0.027). The mean serum HDL-C was significantly increased 13.31 mg/dL in group A and 5.89 mg/dl in group B (P < 0.001). Conclusions: Pioglitazone seems to be a safe drug for reducing serum lipids and CRP in kidney transplant receivers with diabetes mellitus in short term. Long term effect of this drug could be evaluated in future studies. Copyright © 2015 The Author(s)

Gut modulator effects of Conyza bonariensis explain its traditional use in constipation and diarrhea

BACKGROUND AND OBJECTIVES: The current investigation was carried out to explore the pharmacological basis of the crude extract of Conyza bonariensis (Cb.Cr) for its use in constipation and diarrhea. MATERIALS AND METHODS: The plant extract of Conyza bonariensis (C. bonariensis) was prepared, isolated guinea-pig ileum and rabbit jejunum preparations were used to evaluate its gut modulator effects. RESULTS: The Cb.Cr (0.3-10 mg/mL) exhibited spasmogenic effect in isolated guinea-pig ileum preparation, which was about 19-84% of the acetylcholine maximum. Pretreatment of the tissues with atropine (0.1 µM) abolished the contractile effect, similar to acetylcholine. Among the fractions, only the butanol fraction exhibited atropine sensitive contractile effect. In isolated rabbit jejunum preparations, Cb.Cr produced appreciable atropine-sensitive spasmogenic effect at lower concentrations (0.03-0.3 mg/mL) followed by spasmolytic effect at next higher concentration (1.0 and 3.0 mg/mL). Cb.Cr caused an inhibition of the high K+ induced contraction in isolated rabbit jejunum preparation with EC50 value of 0.62 mg/mL. Similarly, verapamil, a standard calcium blocker, inhibited high K+ induced contraction in isolated rabbit jejunum preparations. Cb.Cr caused a right ward shift in the Ca++ concentration response curve, similar to verapamil. Among various fractions of C. bonariensis, only hexane and ethylacetate fractions showed spasmolytic effects. CONCLUSIONS: The crude extract of C. bonariensis contains spasmogenic and spasmolytic constituents, which explains its medicinal use in constipation and diarrhe

Altered platelet activating factor metabolism in insulin dependent diabetes mellitus

Diabetes mellitus is associated with several abnormalities of platelet function. Recent studies have shown that the blood level of platelet activating factor (PAF), a potent inducer of platelet aggregation, is elevated in insulin dependent diabetes mellitus (IDDM) and remains unchanged in non-insulin dependent diabetes mellitus (NIDDM) patients. However, the mechanism of this increase in PAF levels has not been determined. In this study we have measured the activity of plasma PAF acetylhydrolase (an enzyme that regulates PAF levels) and lipoprotein levels in control subjects and diabetic patients. The data presented show that plasma PAF acetylhydrolase activity is significantly decreased in IDDM and is not altered in NIDDM patients. The lipoprotein levels were similar in control and diabetic subjects and there was no correlation between lipoprotein levels and PAF acetylhydrolase activity. These results suggest that the elevated levels of PAF in IDDM patients could be due to a decrease in plasma PAF acetylhydrolase activity

Possible presence of calcium channel blocker(s) in Rubia cordifolia: An indigenous medicinal plant

Crude extract of Rubia cordifolia (RC) was tested in isolated tissue preparations for its possible calcium channel antagonistic activity. RC suppressed the spontaneous contractions of guinea-pig atria, rabbit jejunum and rat uterus in a concentration dependent manner (0.1-3 mg/ml). In rabbit aorta, it inhibited norepinephrine (10 microM) and KCl (80 mM) induced contractions. Replacement of physiological salt solution with calcium free solution abolished the spontaneous movements of rabbit jejunum. However, addition of calcium (25 micrograms/ml) in the tissue bath restored the spontaneous movements. When the tissues were pretreated with plant extract (1 mg/ml) or verapamil (0.5 microgram/ml), addition of calcium failed to restore spontaneous contractions. These results indicate that the plant extract exhibits spasmolytic activity similar to that of verapamil suggestive of presence of calcium channel blocker like constituent(s) in this plant

EPIdemiology of Surgery-Associated Acute Kidney Injury (EPIS-AKI): Study protocol for a multicentre, observational trial

Introduction More than 300 million surgical procedures are performed each year. Acute kidney injury (AKI) is a common complication after major surgery and is associated with adverse short-term and long-term outcomes. However, there is a large variation in the incidence of reported AKI rates. The establishment of an accurate epidemiology of surgery-associated AKI is important for healthcare policy, quality initiatives, clinical trials, as well as for improving guidelines. The objective of the Epidemiology of Surgery-associated Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after major surgery using the latest Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI. Methods and analysis EPIS-AKI is an international prospective, observational, multicentre cohort study including 10 000 patients undergoing major surgery who are subsequently admitted to the ICU or a similar high dependency unit. The primary endpoint is the incidence of AKI within 72 hours after surgery according to the KDIGO criteria. Secondary endpoints include use of renal replacement therapy (RRT), mortality during ICU and hospital stay, length of ICU and hospital stay and major adverse kidney events (combined endpoint consisting of persistent renal dysfunction, RRT and mortality) at day 90. Further, we will evaluate preoperative and intraoperative risk factors affecting the incidence of postoperative AKI. In an add-on analysis, we will assess urinary biomarkers for early detection of AKI. Ethics and dissemination EPIS-AKI has been approved by the leading Ethics Committee of the Medical Council North Rhine-Westphalia, of the Westphalian Wilhelms-University Münster and the corresponding Ethics Committee at each participating site. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and used to design further AKI-related trials. Trial registration number NCT04165369

Bias in MRI Measurements of Apparent Diffusion Coefficient and Kurtosis: Implications for Choice of Maximum Diffusion Encoding

Tissue water diffusion is non-Gaussian and the expressions used to calculate diffusion parameters are approximations which introduce systematic errors dependent on the maximum diffusion encoding, diffusion time, etc. This study aimed at characterizing biases in estimates of both apparent diffusion coefficient and kurtosis, and determines their dependence on these parameters. Similar to the approach of several previous studies, Taylor expansion of the diffusion signal was used to calculate biases. Predicted errors were compared with data from one volunteer. Predicted errors agreed well with the measured errors and also the published diffusion tensor imaging measurements. The equations derived predict biases in measured diffusion parameters and explain much of the discrepancy between measurements obtained with different acquisition protocols. The equations may also be used to choose appropriate diffusion encoding for diffusion weighted, tensor, and kurtosis imaging