Read by QxMD icon Read


Tathyana Mar Amorim Franco, Subray S Hegde, John S Blanchard
The biosynthetic pathway of the branched-chain amino acids is essential for M. tuberculosis growth and survival. We report here the kinetic and chemical mechanism of the pyridoxal 5'-phosphate (PLP)-dependent branched-chain aminotransferase, IlvE, from M. tuberculosis (MtIlvE). This enzyme is responsible for the final step of the synthesis of the branched-chain amino acids isoleucine, leucine and valine. As seen in other aminotransferases, MtIlvE displays a ping-pong kinetic mechanism. pK values were identified from the pH dependence on V as well as V/K, indicating that the phosphate ester of the PLP cofactor, as well as the α-amino group from L-glutamate and the active site Lys204, play roles in acid-base catalysis and binding, respectively...
October 25, 2016: Biochemistry
Lisa N McAuliffe, Kieran N Kilcawley, Jeremiah J Sheehan, Paul L H McSweeney
Liposome-encapsulated ethylenediaminetetraacetic acid (EDTA) was incorporated into a model miniature Gouda-type cheese (20 g) in order to assess its effect on rennet gelation, starter viability, pH, and moisture content. EDTA was encapsulated within 2 different food-grade proliposome preparations, Pro-Lipo Duo and Pro-Lipo C (50% and 40% unsaturated soybean phospholipids and 50% and 60% aqueous medium, respectively), using the following high-shear technologies: Ultra-Turrax (5000 rpm), 2-stage homogenization (345 bar), or microfluidization (690 bar)...
October 25, 2016: Journal of Food Science
Sabina Martí Gamboa, Olga Redrado Giménez, Jara Pascual Mancho, María Lapresta Moros, Julia Ruiz Sada, Sergio Castan Mateo
Objective The objective of this study was to determine ability to detect neonatal acidemia and interobserver agreement with the FIGO 3-tier and 5-tier fetal heart rate (FHR) classification systems. Design This was a case-control study. Setting This study was set at the University Medical Center. Population A total of 202 FHR tracings of 102 women who delivered an acidemic fetus (umbilical arterial cord gas pH ≤ 7.10 and BE < - 8) and 100 who delivered a nonacidemic fetus (umbilical arterial cord gas pH > 7...
October 25, 2016: American Journal of Perinatology
Dae Woo Park, Andrea Sebastiani, Choon Hwai Yap, Marc A Simon, Kang Kim
Mechanical and structural changes of right ventricular (RV) in response to pulmonary hypertension (PH) are inadequately understood. While current standard biaxial testing provides information on the mechanical behavior of RV tissues using surface markers, it is unable to fully assess structural and mechanical properties across the full tissue thickness. In this study, the mechanical and structural properties of normotensive and pulmonary hypertension right ventricular (PHRV) myocardium through its full thickness were examined using mechanical testing combined with 3D ultrasound speckle tracking (3D-UST)...
2016: PloS One
Max Schelker, Caroline Maria Mair, Fabian Jolmes, Robert-William Welke, Edda Klipp, Andreas Herrmann, Max Flöttmann, Christian Sieben
After endocytic uptake, influenza viruses transit early endosomal compartments and eventually reach late endosomes. There, the viral glycoprotein hemagglutinin (HA) triggers fusion between endosomal and viral membrane, a critical step that leads to release of the viral segmented genome destined to reach the cell nucleus. Endosomal maturation is a complex process involving acidification of the endosomal lumen as well as endosome motility along microtubules. While the pH drop is clearly critical for the conformational change and membrane fusion activity of HA, the effect of intracellular transport dynamics on the progress of infection remains largely unclear...
October 2016: PLoS Computational Biology
Nicolas Nguyen Van Long, Valérie Vasseur, Louis Coroller, Philippe Dantigny, Sophie Le Panse, Amélie Weill, Jérôme Mounier, Karim Rigalma
Conidial germination and mycelial growth are generally studied with conidia produced under optimal conditions to increase conidial yield. Nonetheless, the physiological state of such conidia most likely differs from those involved in spoilage of naturally contaminated food. The present study aimed at investigating the impact of temperature, pH and water activity (aw) during production of conidia on the germination parameters and compatible solutes of conidia of Penicillium roqueforti and Penicillium expansum...
October 18, 2016: International Journal of Food Microbiology
V L Shirokova, A M L Enright, C B Kennedy, F G Ferris
This investigation evaluates spatial relationships between summer (July) groundwater temperatures and Fe(II)/Fe(III) biogeochemical cycling over a five year period in a shallow pristine sand aquifer at Meilleurs Bay near Deep River, Ontario, Canada. A warm subsurface thermal island of 12.5-16.1 °C, compared to background conditions of 10-11 °C, was manifest in contour maps of average groundwater temperature over the study period. The warm zone coincided with an area of convergent groundwater flow, implicating horizontal heat transfer by advective convection as the reason for elevated temperatures...
October 19, 2016: Water Research
Shawn M Lyons, Paul Anderson
In this issue of Developmental Cell, Audas et al. (2016) report non-membrane-enclosed amyloid bodies (ABs) assembled in the nuclei of cells exposed to heat and low pH. Remarkably, ABs form not by liquid-to-liquid phase separation, implicated in RNA-seeded granule assembly, but by an amyloidogenic process that promotes a liquid-to-solid transition.
October 24, 2016: Developmental Cell
Sai Zheng, Jia-Chen Shi, Jian-Ying Hu, Wen-Xin Hu, Jing Zhang, Bing Shao
The reaction kinetics and transformation pathways between bisphenol F (BPF) and sodium hypochlorite were investigated at pH values ranging from 6.5 to 8.5 and with different initial concentration ratios. The reaction rate was pH- and free available chlorine (FAC)-dependent: the reaction rate at pH 8.5 was almost 10 times than that at pH 6.5. A total of 40 compounds were tentatively identified as chloro-substituted BPF and polyphenolic compounds by liquid chromatography quadrupole time-of-flight mass spectrometry operating in electrospray ionization mode (LC-ESI-Q-ToF), and 4 main byproducts were confirmed by (1)H and (13)C nuclear magnetic resonance (NMR)...
October 19, 2016: Water Research
Kyle Mock, Jessica Keeley, Ashkan Moazzez, David S Plurad, Brant Putnam, Dennis Y Kim
The population of the United States is predicted to age dramatically over the next few decades; as such older patients will comprise an increasing proportion of the injured populations. Due to multiple comorbidities and frailty, the old and very old are at greater risk for mortality than younger patients. To identify predictors of inhospital mortality in these patients, we performed a retrospective cohort study at our Level 1 trauma center. Between April 2009 and October 2014, we identified 193 trauma patients aged 80 years and older admitted to the intensive care unit...
October 2016: American Surgeon
Blanka Bucsella, Antoine Fornage, Catherine Le Denmat, Franka Kálmán
In biotechnological processes the intracellular level of nucleotides and nucleotide sugars have a direct impact on the post-translational modification (glycosylation) of the therapeutic protein products and on the exopolysaccharide pattern of the cells. Thus, they are precursors and also key components in the production of glycoproteins and glycolipids. All four nucleotides (at different phosphorylation stages) and their natural sugar derivatives coexist in biological samples. Their relative ratios depend on the actual conditions under which the cells are grown...
October 2016: Chimia
Francisco Javier Montes Ruiz-Cabello, Tamas Oncsik, Miguel A Rodríguez-Valverde, Plinio Maroni, Miguel A Cabrerizo-Vílchez
Colloidal interactions have been extensively studied due to the wide number of applications where colloids are present. In general, the electric double layer force and the van der Waals interaction dominate the net force acting between two colloids at large separation distances. However, it is well accepted that some other phenomena, especially those acting at short separation distances, might be relevant and induce substantial changes in the force profiles. Within these phenomena, those related to the surface contact angle, the hydration degree of the ions or the pH, may dominate the force profiles features, not only at short distances...
October 25, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Samuel L Esarey, Joel C Holland, Bart M Bartlett
We analyze the stability of the non-heme water oxidation catalyst (WOC), Fe(bpmcn)Cl2 toward oxygen and illumination under nonaqueous and acidic conditions. Fe(bpmcn)Cl2 has been previously used as a C-H activation catalyst, a homogeneous WOC, and as a cocatalyst anchored to WO3 for photoelectrochemical water oxidation. This paper reports that the ligand dissociates at pH 1 with a rate constant k = 19.8(2) × 10(-3) min(-1), resulting in loss of catalytic activity. The combination of UV-vis experiments, (1)H NMR spectroscopy, and cyclic voltammetry confirm free bpmcn and Fe(2+) present in solution under acidic conditions...
October 25, 2016: Inorganic Chemistry
Jeng-Haur Chen, Weiyi Xu, David N Sheppard
Cystic fibrosis transmembrane conductance regulator (CFTR) is an ATP-gated Cl(-) channel defective in the genetic disease cystic fibrosis (CF). The gating behaviour of CFTR is characterized by bursts of channel openings interrupted by brief, flickery closures, separated by long closures between bursts. Entry to and exit from an open burst is controlled by the interaction of ATP with two ATP-binding sites, sites 1 and 2 in CFTR. To understand better the kinetic basis of CFTR intraburst gating, we investigated the single-channel activity of human CFTR at different intracellular pH (pHi ) values...
October 25, 2016: Journal of Physiology
Boris Shenkman, Ivan Budnik, Yulia Einav, Hagit Hauschner, Mykhaylo Andrejchin, Uriel Martinowitz
BACKGROUND: Trauma-induced coagulopathy (TIC) is commonly seen among patients with severe injury. The dynamic process of TIC is characterized by variability of the features of the disease. METHODS: A model of TIC was created. Hemodilution was produced by mixing the blood with 40% TRIS/saline solution, fibrinolysis by treating the blood with 160 ng/mL tPA, acidosis by adding 1.2 mg/mL lactic acid achieving pH 7.0-7.1, and hypothermia by running the assay at 31 °C...
October 25, 2016: Journal of Trauma and Acute Care Surgery
Bijan S Kheirabadi, Nahir Miranda, Irasema B Terrazas, Mary D Gonzales, Rose C Grimm, Michael A Dubick
INTRODUCTION: Prehospital, small-volume resuscitation of combat casualties with a synthetic colloid [6% hydroxyethyl starch (HES) 670/0.75] has been recommended when blood or blood components are unavailable. We studied hemostatic effects of a newer synthetic colloid (6% HES 130/0.4,) compared to either a natural colloid (albumin) or to crystalloids in an uncontrolled hemorrhage model. METHODS: Spontaneously breathing NZW rabbits (3.4±0.1 kg) were anesthetized, instrumented and subjected to a splenic injury with uncontrolled bleeding...
October 25, 2016: Journal of Trauma and Acute Care Surgery
Christoph Töpper, Cathérine Louise Steinbach, Christoph Dorn, Alexander Kratzer, Sebastian G Wicha, Michael Schleibinger, Uwe Liebchen, Frieder Kees, Bernd Salzberger, Martin G Kees
BACKGROUND: Standard doses of linezolid may not be suitable for all patient groups. ICU patients in particular may be at risk of inadequate concentrations. This study investigated variability of drug exposure and its potential sources in this population. PATIENTS AND METHODS: Plasma concentrations of linezolid were determined by HPLC in a convenience sample of 20 ICU patients treated with intravenous linezolid 600 mg twice daily. Ultrafiltration applying physiological conditions (pH 7...
October 24, 2016: Therapeutic Drug Monitoring
Sudip Das, Tarak Karmakar, Sundaram Balasubramanian
Thermomyces lanuginosus lipase (TLL) is an industrially significant catalyst for the production of biodiesel due to its operability over a wide range of pH and temperature. Molecular dynamics simulations of TLL in aqueous solutions of a biocompatible ionic liquid (IL), cholinium glycinate (ChGly) have been carried out to investigate the microscopic reasons for the experimentally observed enhancement in the activity of TLL, upon addition of room temperature IL, especially at an optimal concentration. Eight different TLL systems in both its open and closed forms at various concentrations of the room temperature IL in water have been studied...
October 25, 2016: Journal of Physical Chemistry. B
Min-Ju Seo, Woo-Ri Kang, Kyung-Chul Shin, Deok-Kun Oh
The reaction conditions for the production of 7S,8S-dihydroxy-9,12(Z,Z)-octadecadienoic acid from linoleic acid by recombinant Escherichia coli expressing 7,8-linoleate diol synthase from Glomerella cingulata were optimized using response surface methodology. The optimal reaction conditions were pH 7.0, 18.6 °C, 10.8% (v/v) dimethyl sulfoxide, 44.9 g/L cells, and 14.3 g/L linoleic acid, with agitation at 256 rpm. Under these conditions, recombinant cells produced 7,8-dihydroxy unsaturated fatty acids in the range of 7...
October 25, 2016: Journal of Agricultural and Food Chemistry
Peifang Wang, Chuangfei Wu, Yong Guo, Chao Wang
Wheat straw-derived biochar (BC-4-700) with a large surface area (2263.10 m(2) g(-1)) has been synthesized using potassium hydroxide as an activating agent, and its sorption performance is evaluated by sorbing methylene blue (MB) and methyl orange (MO). The sorption behaviours of both MO and MB by BC-4-700 all follow pseudo-second-order and Langmuir models, and the driving forces for the two sorptions are attributed to the pi-pi interaction. The largest sorption quantity for MO by BC-4-700 is 3.24 mmol g(-1), being 1...
October 25, 2016: Physical Chemistry Chemical Physics: PCCP
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"