Read by QxMD icon Read


S-F Zhou, J-B Yin, H Yang, J Zhong, P An
OBJECTIVE: To explore the imaging characteristics and clinical application value of gastric filling ultrasound combined with an intravenous contrast agent (double contrast ultrasonography, DCUS) in the diagnosis of advanced gastric carcinoma. PATIENTS AND METHODS: Totally 48 patients with advanced gastric carcinoma were confirmed by endoscopic biopsy and then administrated with DCUS and enhanced magnetic resonance examination before treatment. Retrospective analysis was conducted based on the characteristics of their ultrasonic images, and the results of diagnosis were compared and analyzed between the DCUS technology and the enhanced magnetic resonance examination...
July 2016: European Review for Medical and Pharmacological Sciences
Gottfried Unden, Alexander Strecker, Alexandra Kleefeld, Ok Bin Kim
C4-dicarboxylates and the C4-dicarboxylic amino acid l-aspartate support aerobic and anaerobic growth of Escherichia coli and related bacteria. In aerobic growth, succinate, fumarate, D- and L-malate, L-aspartate, and L-tartrate are metabolized by the citric acid cycle and associated reactions. Because of the interruption of the citric acid cycle under anaerobic conditions, anaerobic metabolism of C4-dicarboxylates depends on fumarate reduction to succinate (fumarate respiration). In some related bacteria (e...
June 2016: EcoSal Plus
Sebastian Wörner, Alexander Strecker, Christian Monzel, Matthias Zeltner, Julian Witan, Andrea Ebert-Jung, Gottfried Unden
The sensor kinase DcuS of Escherichia coli co-operates under aerobic conditions with the C4 -dicarboxylate transporter DctA to form the DctA/DcuS sensor complex. Under anaerobic conditions C4 -dicarboxylate transport in fumarate respiration is catalyzed by C4 -dicarboxylate/fumarate antiporter DcuB. (i) DcuB interacted with DcuS as demonstrated by a bacterial two-hybrid system (BACTH) and by co-chromatography of the solubilized membrane-proteins (mHPINE assay). (ii) In the DcuB/DcuS complex only DcuS served as the sensor since mutations in the substrate site of DcuS changed substrate specificity of sensing, and substrates maleate or 3-nitropropionate induced DcuS response without affecting the fumarate site of DcuB...
December 2016: Environmental Microbiology
G Unden, S Wörner, C Monzel
Many membrane-bound sensor kinases require accessory proteins for function. The review describes functional control of membrane-bound sensors by transporters. The C4-dicarboxylate sensor kinase DcuS requires the aerobic or anaerobic C4-dicarboxylate transporters DctA or DcuB, respectively, for function and forms DctA/DcuS or DcuB/DcuS sensor complexes. Free DcuS is in the permanent (ligand independent) ON state. The DctA/DcuS and DcuB/DcuS complexes, on the other hand, control expression in response to C4-dicarboxylates...
2016: Advances in Microbial Physiology
Xue-Yue Ji, Chun-Nan Fei, Ying Zhang, Wei Zhang, Jun Liu, Jie Dong
INTRODUCTION: Dental unit waterline (DUWL) output water is delivered through instruments of a dental chair unit (DCU) to irrigate and cool teeth. However, these waterlines can be heavily contaminated with bacteria. AIM: The purpose of the present study was to assess retraction and investigate the contamination level and prevalence of bacteria in DUWL output water. METHODS: Fifty-eight DCUs were randomly selected from 30 hospitals in 10 districts of Tianjin, one of the four special municipalities of China...
August 2016: International Dental Journal
Larry Reitzer
Glutamate, aspartate, asparagine, L-alanine, and D-alanine are derived from intermediates of central metabolism, mostly the citric acid cycle, in one or two steps. While the pathways are short, the importance and complexity of the functions of these amino acids befit their proximity to central metabolism. Inorganic nitrogen (ammonia) is assimilated into glutamate, which is the major intracellular nitrogen donor. Glutamate is a precursor for arginine, glutamine, proline, and the polyamines. Glutamate degradation is also important for survival in acidic environments, and changes in glutamate concentration accompany changes in osmolarity...
December 2004: EcoSal Plus
Ramón De las Peñas, Santiago Ponce, Fernando Henao, Carlos Camps Herrero, Enric Carcereny, Yolanda Escobar Álvarez, César A Rodríguez, Juan Antonio Virizuela, Rafael López López
Hyponatremia (Na ˂ 135 mmol/l) is the most frequent electrolyte disorder in clinical practice, and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) is the commonest cause of hyponatremia in cancer patients. Correcting hyponatremia in these patients can reduce morbidity and mortality, increase the response to anti-cancer agents, and help reduce hospital length of stay and costs. Tolvaptan is an oral medication used to treat SIADH-related hyponatremia patients that needs to be initiated at hospital so patients can have their serum sodium monitored...
January 2016: Supportive Care in Cancer: Official Journal of the Multinational Association of Supportive Care in Cancer
Sabrina Graf, Constanze Broll, Juliane Wissig, Alexander Strecker, Maria Parowatkin, Gottfried Unden
The thermophilic Geobacillus thermodenitrificans and Geobacillus kaustophilus are able to use citrate or C4-dicarboxylates like fumarate or succinate as the substrates for growth. The genomes of the sequenced Geobacillus strains (nine strains) each encoded a two-component system of the CitA family. The sensor kinase of G. thermodenitrificans (termed CitAGt) was able to replace CitA of Escherichia coli (CitAEc) in a heterologous complementation assay restoring expression of the CitAEc-dependent citC-lacZ reporter gene and anaerobic growth on citrate...
January 2016: Microbiology
Fatima Abdouchakour, Chloé Dupont, Delphine Grau, Fabien Aujoulat, Patricia Mournetas, Hélène Marchandin, Sylvie Parer, Philippe Gibert, Jean Valcarcel, Estelle Jumas-Bilak
Dental care unit waterlines (DCUWs) consist of complex networks of thin tubes that facilitate the formation of microbial biofilms. Due to the predilection toward a wet environment, strong adhesion, biofilm formation, and resistance to biocides, Pseudomonas aeruginosa, a major human opportunistic pathogen, is adapted to DCUW colonization. Other nonfermentative Gram-negative bacilli, such as members of the genus Achromobacter, are emerging pathogens found in water networks. We reported the 6.5-year dynamics of bacterial contamination of waterlines in a dental health care center with 61 dental care units (DCUs) connected to the same water supply system...
November 2015: Applied and Environmental Microbiology
Christian Monzel, Gottfried Unden
The C4-dicarboxylate sensor kinase DcuS is membrane integral because of the transmembrane (TM) helices TM1 and TM2. Fumarate-induced movement of the helices was probed in vivo by Cys accessibility scanning at the membrane-water interfaces after activation of DcuS by fumarate at the periplasmic binding site. TM1 was inserted with amino acid residues 21-41 in the membrane in both the fumarate-activated (ON) and inactive (OFF) states. In contrast, TM2 was inserted with residues 181-201 in the OFF state and residues 185-205 in the ON state...
September 1, 2015: Proceedings of the National Academy of Sciences of the United States of America
M A Boyle, M J O'Donnell, R J Russell, N Galvin, J Swan, D C Coleman
OBJECTIVES: Decontaminating dental chair unit (DCU) suction systems in a convenient, safe and effective manner is problematic. This study aimed to identify and quantify the extent of the problems using 25 DCUs, methodically eliminate these problems and develop an efficient approach for reliable, effective, automated disinfection. METHODS: DCU suction system residual contamination by environmental and human-derived bacteria was evaluated by microbiological culture following standard aspiration disinfection with a quaternary ammonium disinfectant or alternatively, a novel flooding approach to disinfection...
October 2015: Journal of Dentistry
W Ben Mortenson, Anne Marie Bishop
Specialized dementia care units (DCUs) house individuals whose behaviors cannot be managed in other settings. To ensure environmental fit, admission/discharge criteria are recommended for DCUs; however, there is no consensus about what criteria should be used. This study aimed to describe, in a random sample of DCUs, the current admission criteria, current/recommended discharge criteria, and services to support discharge. Usable surveys were returned by 23 of 30 facilities. Residents were most frequently admitted because they had a diagnosis of dementia and exhibited cognitive/behavioral problems...
March 2016: Journal of Applied Gerontology: the Official Journal of the Southern Gerontological Society
José A Reyes-Darias, Yiling Yang, Victor Sourjik, Tino Krell
The PctA and PctB chemoreceptors of Pseudomonas aeruginosa mediate chemotaxis toward amino acids. A general feature of signal transduction processes is that a signal input is converted into an output. We have generated chimeras combining the Tar signaling domain with either the PctA or PctB ligand binding domain (LBD). Escherichia coli harboring either PctA-Tar or PctB-Tar mediated chemotaxis toward amino acids. The responses of both chimeras were determined using fluorescence resonance energy transfer, and the derived EC50 values are a measure of output...
May 2015: Molecular Microbiology
Patrick D Scheu, Philipp A Steinmetz, Felix Dempwolff, Peter L Graumann, Gottfried Unden
The C4-dicarboxylate responsive sensor kinase DcuS of the DcuS/DcuR two-component system of E. coli is membrane-bound and reveals a polar localization. DcuS uses the C4-dicarboxylate transporter DctA as a co-regulator forming DctA/DcuS sensor units. Here it is shown by fluorescence microscopy with fusion proteins that DcuS has a dynamic and preferential polar localization, even at very low expression levels. Single assemblies of DcuS had high mobility in fast time lapse acquisitions, and fast recovery in FRAP experiments, excluding polar accumulation due to aggregation...
2014: PloS One
Irisappan Ganesh, Sambandam Ravikumar, Ik-Keun Yoo, Soon Ho Hong
In an attempt to develop a high-throughput screening system for screening microorganisms which produce high amounts of malate, a MalKZ chimeric HK-based biosensor was constructed. Considering the sequence similarity among Escherichia coli (E. coli) MalK with Bacillus subtilis MalK and E. coli DcuS, the putative sensor domain of MalK was fused with the catalytic domain of EnvZ. The chimeric MalK/EnvZ TCS induced the ompC promoter through the cognate response regulator, OmpR, in response to extracellular malate...
April 2015: Bioprocess and Biosystems Engineering
Philipp Aloysius Steinmetz, Sebastian Wörner, Gottfried Unden
The C4-dicarboxylate responsiveness of the sensor kinase DcuS is only provided in concert with C4-dicarboxylate transporters DctA or DcuB. The individual roles of DctA and DcuS for the function of the DctA/DcuS sensor complex were analysed. (i) Variant DctA(S380D) in the C4-dicarboxylate site of DctA conferred C4-dicarboxylate sensitivity to DcuS in the DctA/DcuS complex, but was deficient for transport and for growth on C4-dicarboxylates. Consequently transport activity of DctA is not required for its function in the sensor complex...
October 2014: Molecular Microbiology
Irisappan Ganesh, Sambandam Ravikumar, Seung Hwan Lee, Si Jae Park, Soon Ho Hong
DcuS/DcuR two component system (TCS) was firstly employed for the expression of the gfp gene under the dcuB gene promoter in aerobic condition to develop high throughput screening system able to screen microorganisms producing high amount of fumarate. However, the DcuS/DcuR TCS could not produce a signal strong enough to mediate the expression of the gfp gene responding fumarate concentration. Thus, DcuS/DucR TCS was engineered by recruiting the EnvZ/OmpR system, the most-studied TCS in E. coli. A chimeric DcuS/EnvZ (DcuSZ) TCS was constructed by fusing the sensor histidine kinase of DcuS with the cytoplasmic catalytic domain of EnvZ, in which the expression of the gfp gene or the ompC gene was mediated by the ompC gene promoter through the cognate response regulator, OmpR...
December 2013: Journal of Biotechnology
Christian Monzel, Pia Degreif-Dünnwald, Christina Gröpper, Christian Griesinger, Gottfried Unden
The cytoplasmic PASC domain of the fumarate responsive sensor kinase DcuS of Escherichia coli links the transmembrane to the kinase domain. PASC is also required for interaction with the transporter DctA serving as a cosensor of DcuS. Earlier studies suggested that PASC functions as a hinge and transmits the signal to the kinase. Reorganizing the PASC dimer interaction and, independently, removal of DctA, converts DcuS to the constitutive ON state (active without fumarate stimulation). ON mutants were categorized with respect to these two biophysical interactions and the functional state of DcuS: type I-ON mutations grossly reorganize the homodimer, and decrease interaction with DctA...
December 2013: MicrobiologyOpen
Neethu Shah, Rosmarie Gaupp, Hideaki Moriyama, Kent M Eskridge, Etsuko N Moriyama, Greg A Somerville
BACKGROUND: The Per-Arnt-Sim (PAS) domain represents a ubiquitous structural fold that is involved in bacterial sensing and adaptation systems, including several virulence related functions. Although PAS domains and the subclass of PhoQ-DcuS-CitA (PDC) domains have a common structure, there is limited amino acid sequence similarity. To gain greater insight into the evolution of PDC/PAS domains present in the bacterial kingdom and staphylococci in specific, the PDC/PAS domains from the genomic sequences of 48 bacteria, representing 5 phyla, were identified using the sensitive search method based on HMM-to-HMM comparisons (HHblits)...
2013: BMC Genomics
Miriam Rico-Jiménez, Francisco Muñoz-Martínez, Cristina García-Fontana, Matilde Fernandez, Bertrand Morel, Alvaro Ortega, Juan Luis Ramos, Tino Krell
The paralogous receptors PctA, PctB and PctC of Pseudomonas aeruginosa were reported to mediate chemotaxis to amino acids, intermediates of amino acid metabolism and chlorinated hydrocarbons. We show that the recombinant ligand binding regions (LBRs) of PctA, PctB and PctC bind 17, 5 and 2 l-amino acids respectively. In addition, PctC-LBR recognized GABA but not any other structurally related compound. l-Gln, one of the three amino acids that is not recognized by PctA-LBR, was the most tightly binding ligand to PctB suggesting that PctB has evolved to mediate chemotaxis primarily towards l-Gln...
June 2013: Molecular Microbiology
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"