Sources of polychlorinated dibenzo-p-dioxins and -furans to sediment in the Newtown Creek Superfund Site.

Polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs) are contaminants of concern in the New York/New Jersey Harbor and in the organisms of the Newtown Creek Superfund site, which lies within the harbor. Because PCDD/Fs are never intentionally produced, identifying their sources can be challenging. In this work, sources of PCDD/Fs to the sediment of Newtown Creek were investigated using Positive Matrix Factorization (PMF) to analyze two data sets containing data on concentrations of (1) PCDD/Fs and (2) PCDD/Fs plus polychlorinated biphenyls (PCBs).

Source apportionment of polychlorinated biphenyls in the sediment of the Newtown Creek superfund site.

Polychlorinated biphenyls (PCBs) are a primary contaminant of potential concern at the Newtown Creek superfund site. Measurements of PCBs in hundreds of samples of sediment (surface and cores) within Newtown Creek and at nearby reference locations were obtained from the Remedial Investigation (RI) databases. This data set was analyzed using Positive Matrix Factorization (PMF).

A Unique Sequence Is Essential for Efficient Multidrug Efflux Function of the MtrD Protein of .

Antimicrobial resistance in Neisseria gonorrhoeae has reached an alarming level, severely impacting the effective treatment of gonorrhea. Belonging to the resistance-nodulation-cell division (RND) superfamily of efflux transporters, the MtrD membrane protein of N. gonorrhoeae provides resistance to a broad range of antimicrobial compounds.

Coordination of Substrate Binding and Protonation in the MtrD Efflux Pump Controls the Functionally Rotating Transport Mechanism.

Multidrug resistance is a serious problem that threatens the effective treatment of the widespread sexually transmitted disease gonorrhea, caused by the Gram-negative bacterium . The drug efflux pump primarily implicated in antimicrobial resistance is the inner membrane transporter MtrD, which forms part of the tripartite multiple transferable resistance (Mtr) CDE efflux system. A structure of MtrD was first solved in 2014 as a symmetrical homotrimer, and then, recently, as an asymmetrical homotrimer.

Sources of polychlorinated biphenyls to Upper Hudson River sediment post-dredging.

The Upper Hudson River (UHR) has been contaminated with polychlorinated biphenyls (PCBs) since the 1940s due to the manufacture of capacitors at two plants near Hudson Falls and Fort Edward, NY by General Electric (GE). Dredging of portions of the UHR was conducted from 2009 to 2015 as a partial remedy for this contamination. In 2017, the New York State Department of Environmental Conservation undertook a comprehensive post-dredging survey of sediment contamination in the UHR.

Isolating different natural and anthropogenic PAHs in the sediments from the northern Bering-Chukchi margin: Implications for transport processes in a warming Arctic.

Polycyclic aromatic hydrocarbons (PAHs) have become the dominating burden in the Arctic ecosystems, but their transport pathways and relative importance of different sources in the Arctic remained unclear, and this would be further complicated by climate change. Here we interpreted 27 PAHs in 34 surface sediments from the northern Bering-Chukchi margin. We integrated source apportionment methods (including diagnostic ratios, principal component analysis, hierarchical analysis, and positive matrix factorization (PMF) model) together with geochemistry parameters, which reveal a gradually clear picture of the spatial patterns of different sources.

Perfluoroalkyl substances in sediments from the Bering Sea to the western Arctic: Source and pathway analysis.

Although perfluoroalkyl substances (PFASs) are ubiquitous in the Arctic, their dominant pathways to the Arctic remain unclear. Most modeling studies support major oceanic transport for PFASs in the Arctic seawater, but this conclusion contradicts the rapid response of PFASs to global emissions in some biota species. Sediments, which act as important PFAS sinks for seawater and potential PFAS source to the benthic food web, are important for interpreting the fate of PFASs in the Arctic.

Impact of an initial random magnetic field on the evolution of two-dimensional shearless mixing layers.

The impact of an initial random magnetic field on the temporal evolution of a two-dimensional incompressible turbulent shearless mixing layer is investigated using direct numerical simulation. Different intensities of the initial random magnetic field are imposed with uniform probability distribution on an identical flow field. The initial flow field condition is the turbulent shearless mixing layer with different kinetic energy ratio (E_{H}/E_{L}=6.

Multidrug Resistance in Neisseria gonorrhoeae: Identification of Functionally Important Residues in the MtrD Efflux Protein.

A key mechanism that uses to achieve multidrug resistance is the expulsion of structurally different antimicrobials by the MtrD multidrug efflux protein. MtrD resembles the homologous AcrB efflux protein with several common structural features, including an open cleft containing putative access and deep binding pockets proposed to interact with substrates. A highly discriminating strain, with the MtrD and NorM multidrug efflux pumps inactivated, was constructed and used to confirm and extend the substrate profile of MtrD to include 14 new compounds.

Quantified dual energy computed tomography perfusion imaging using myocardial iodine concentration: Validation using CT derived myocardial blood flow and invasive fractional flow reserve in a porcine model.

Background: Myocardial CT perfusion imaging with dual energy (DE-CTP) can produce myocardial iodine perfusion maps. This study evaluated the accuracy of first pass myocardial iodine concentration in DE-CTP compared to CT derived dynamic myocardial blood flow (MBF) to determine regional myocardial ischemia in an animal model of coronary stenosis using invasive Fractional Flow Reserve (FFR).

Methods: Seven anaesthetised pigs (mean weight 51 ± 4 kg) had a graded coronary artery stenosis produced in six vessels (plus one control animal) using a methacrylate plug with FFR recorded in the target artery (ischemia = FFR<0.

Development of a Porcine Model of Coronary Stenosis Using Fully Percutaneous Techniques Suitable For Performing Cardiac Computed Tomography, CT-Perfusion Imaging and Fractional Flow Reserve.

Background: The aim of this study was to develop and describe percutaneous coronary angiographic techniques to create a porcine model of acute coronary stenosis with methacrylate plugs that can by assessed using fractional flow reserve (FFR), invasive coronary angiography and coronary computed tomographic (CT) perfusion imaging without introducing artefacts associated with surgical models.

Methods: Following animal care and institutional approval and using percutaneous coronary catheterisation techniques within an animal laboratory we introduced precision drilled methacrylate plugs into one of the three main coronary arteries of 10 experimental female pigs. Coronary pressure wire measurements were performed across the experimental stenosis for the calculation of FFR.

The role played by drug efflux pumps in bacterial multidrug resistance.

Antimicrobial resistance is a current major challenge in chemotherapy and infection control. The ability of bacterial and eukaryotic cells to recognize and pump toxic compounds from within the cell to the environment before they reach their targets is one of the important mechanisms contributing to this phenomenon. Drug efflux pumps are membrane transport proteins that require energy to export substrates and can be selective for a specific drug or poly-specific that can export multiple structurally diverse drug compounds.

The Effect of Pistacia atlantica Var. mutica Mouthwash on Dental Plaque Bacteria and Subgingival Microorganisms: a Randomized and Controlled Triple-blind Study.

Dental plaque is a well-documented etiologic factor for periodontal diseases. While chlorhexidine (CHX) is the gold-standard agent for treating dental plaques, undesirable side effects are often found after continuous use of the mouthwash. Therefore, this single-center, randomized, triple-blinded and clinical trial was undertaken to evaluate the efficacy of Pistacia atlantica Var.

A genetically encoded and gate for cell-targeted metabolic labeling of proteins.

We describe a genetic AND gate for cell-targeted metabolic labeling and proteomic analysis in complex cellular systems. The centerpiece of the AND gate is a bisected methionyl-tRNA synthetase (MetRS) that charges the Met surrogate azidonorleucine (Anl) to tRNA(Met). Cellular protein labeling occurs only upon activation of two different promoters that drive expression of the N- and C-terminal fragments of the bisected MetRS.

Treatment of postoperative nausea and vomiting after spinal anesthesia for cesarean delivery: A randomized, double-blinded comparison of midazolam, ondansetron, and a combination.

Background: The antiemetic efficacy of midazolam and ondansetron was shown before. The aim of the present study was to compare efficacy of using intravenous midazoalm, ondansetron, and midazolam in combination with ondansetron for treatment of nausea and vomiting after cesarean delivery in parturient underwent spinal anesthesia.

Materials And Methods: ONE HUNDRED THIRTY TWO PARTURIENTS WERE RANDOMLY ALLOCATED TO ONE OF THREE GROUPS: group M (n = 44) that received intravenous midazoalm 30 μg/kg; group O (n = 44) that received intravenous ondansetron 8 mg; group MO (n = 44) that received intravenous midazoalm 30 μg/kg combined with intravenous ondansetron 8 mg if patients had vomiting or VAS of nausea ≥ 3 during surgery (after umbilical cord clamping) and 24 hours after that.

GRID: a high-resolution protein structure refinement algorithm.

The energy-based refinement of protein structures generated by fold prediction algorithms to atomic-level accuracy remains a major challenge in structural biology. Energy-based refinement is mainly dependent on two components: (1) sufficiently accurate force fields, and (2) efficient conformational space search algorithms. Focusing on the latter, we developed a high-resolution refinement algorithm called GRID.

Pulmonary disease caused by Mycobacterium simiae in Iran's national referral center for tuberculosis.

Introduction: Several species of non-tuberculosis mycobacteria (NTM) can affect humans and can cause either symptomatic or asymptomatic infection.  This study aimed to determine the clinical and radiological manifestation, as well as the treatment, of M. simiae in patients in Masih Daneshvari Hospital, a TB referral hospital in Iran.

Prevalence and antimicrobial susceptibility of extended-spectrum beta-lactamase-producing bacteria in intensive care units of Sanandaj general hospitals (Kurdistan, Iran).

This study focused on analyzing the spread of extended-spectrum beta-lactamase (ESBL) enzymes among Gram-negative bacteria at intensive care units (ICUs). Between January 2007 and January 2008, 301 consecutive clinical isolates of Gram-negative type were isolated. Of these, 66 strains were collected from patients in ICUs in two major hospitals in Sanandaj (Kurdistan, Iran).

Importance of timing of magnesium administration in the isolated ischemic-reperfused rat heart: role of K(ATP) channels.

There is a growing interest for the beneficial effect of magnesium (Mg) in cardiovascular disorders. A number of cardiovascular disorders including myocardial infarction, arrhythmias and congestive heart failure have been associated with low extra- cellular or intracellular concentrations of Mg. The efficiency of the preconditioning effect of Mg on cardiac function and infarct size in the globally ischemic-reperfused isolated rat heart was studied together with the role of ATP-sensitive potassium (K(ATP)) channels in protection induced by Mg.

Prevalence and significance of a negative extended-spectrum beta-lactamase (ESBL) confirmation test result after a positive ESBL screening test result for isolates of Escherichia coli and Klebsiella pneumoniae: results from the SENTRY Asia-Pacific Surveillance Program.

A negative extended-spectrum beta-lactamase (ESBL) confirmation test result obtained after a positive ESBL screening test result using Clinical and Laboratory Standards Institute methods has been a common occurrence among isolates of Escherichia coli and Klebsiella pneumoniae in the SENTRY Antimicrobial Surveillance Program in the Asia-Pacific region. Among isolates collected between 1998 and 2004 this screen-positive, nonconfirmed profile (failed to show clavulanate synergy) was observed in 8.9% of 4,515 E.

Culture filtrate of Cryptococcus neoformans var. gattii (CneF) as a novel anti-inflammatory compound in the treatment of experimental septic arthritis.

We examined the efficacy of the culture filtrate of Cryptococcus neoformans var. gattii (CneF) as a novel anti-inflammatory compound in experimental septic arthritis. Haematogenously infectious arthritis was induced in rats by a single intravenous injection of 109 CFU Staphylococcus aureus producing toxic shock syndrome toxin-1.

Effect of granisetron on morphine-induced analgesia in mice by formalin test.

1. In this investigation, the influence of a selective 5HT3 antagonist, granisetron, on morphine-induced antinociception in the formalin test has been studied. There is evidence that the 5HT3 receptor system takes part in analgesic response.