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https://www.readbyqxmd.com/read/28346740/are-various-sigma-hole-bonds-steered-by-the-same-mechanisms
#1
Slawomir Janusz Grabowski, W Andrzej Sokalski
Representative Lewis acid - Lewis base complexes linked by tetrel, pnicogen, chalcogen and halogen bonds have been studied within the Quantum Theory of Atoms in Molecules (QTAIM) approach and the Hybrid Variation-Perturbation Theory (HVPT) in order to analyse possible relationships between these sigma-hole dimers. Results obtained at the MP2/aug-cc-pVTZ level indicate numerous correlations similar to hydrogen bonded systems.
March 27, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28346492/dual-energy-x-ray-absorptiometry-body-composition-reference-values-of-limbs-and-trunk-from-nhanes-1999-2004-with-additional-visualization-methods
#2
Benjamin J Hinton, Bo Fan, Bennett K Ng, John A Shepherd
Body Mass Index has traditionally been used as a measure of health, but Fat Mass Index (FMI) and Lean Mass Index (LMI) have been shown to be more predictive of mortality and health risk. Total body FMI and LMI reference curves have particularly been useful in quantifying sarcopenia and sarcopenic obesity. Research has shown regional composition has significant associations to health outcomes. We derived FMI and LMI reference curves of the regions of the body (leg, arm, and trunk) for 15,908 individuals in the 1999-2004 National Health and Nutrition Examination Survey data for each sex and ethnicity using the Lambda-Mu-Sigma (LMS) method and developed software to visualize this regional composition...
2017: PloS One
https://www.readbyqxmd.com/read/28346244/a-six-sigma-approach-to-analyze-time-to-assembly-variance-of-surgical-trays-in-a-sterile-services-department
#3
Flavio S Fogliatto, Michel J Anzanello, Guilherme L Tortorella, Daniela S S Schneider, Cintia G R Pereira, Beatriz D Schaan
INTRODUCTION: We analyze the assembly of surgical trays in a hospital's sterile services department. The department assembles 520 different tray setups. However, tray assembly times are unknown, imposing a challenge to production planners. To respond to demand, workers from other departments are often called, leading to higher operational costs and more frequent quality problems due to workers' poor training and inconsistency. METHODS: Conducting traditional time-motion studies is infeasible in such a high variety production setting...
March 24, 2017: Journal for Healthcare Quality: Official Publication of the National Association for Healthcare Quality
https://www.readbyqxmd.com/read/28338924/a-nonsynonymous-snp-catalog-of-mycobacterium-tuberculosis-virulence-genes-and-its-use-for-detecting-new-potentially-virulent-sublineages
#4
N E Mikheecheva, M V Zaychikova, A V Melerzanov, V N Danilenko
Mycobacterium tuberculosis is divided into several distinct lineages, and various genetic markers such as IS-elements, VNTR, and SNPs are used for lineage identification. We propose an M. tuberculosis classification approach based on functional polymorphisms in virulence genes. An M. tuberculosis virulence genes catalog has been established, including 319 genes from various protein groups, such as proteases, cell wall proteins, fatty acid and lipid metabolism proteins, sigma factors, toxin-antitoxin systems...
March 11, 2017: Genome Biology and Evolution
https://www.readbyqxmd.com/read/28338490/small-volume-injections-evaluation-of-volume-administration-deviation-from-intended-injection-volumes
#5
Matthew K Muffly, Michael I Chen, Rebecca E Claure, David R Drover, Bradley Efron, William L Fitch, Gregory B Hammer
BACKGROUND: In the perioperative period, anesthesiologists and postanesthesia care unit (PACU) nurses routinely prepare and administer small-volume IV injections, yet the accuracy of delivered medication volumes in this setting has not been described. In this ex vivo study, we sought to characterize the degree to which small-volume injections (≤0.5 mL) deviated from the intended injection volumes among a group of pediatric anesthesiologists and pediatric postanesthesia care unit (PACU) nurses...
March 23, 2017: Anesthesia and Analgesia
https://www.readbyqxmd.com/read/28338476/frank-kasper-sigma-phase-in-polybutadiene-poly-epsilon-caprolactone-diblock-copolymer-polybutadiene-blends
#6
Hideaki Takagi, Ryo Hashimoto, Noriyuki Igarashi, Shunji Kishimoto, Katsuhiro Yamamoto
Microphase-separated structures in a polybutadiene-poly(ε-caprolactone) diblock copolymer (PB-PCL)/polybutadiene homopolymer (PB) blend were investigated by small-angle X-ray scattering (SAXS). Non-equilibrium spherical micelles were observed at temperatures ranging between 60 and 100 °C. An SAXS profile with >60 scattering peaks was recorded at 140 °C. All the peak positions were in good agreement with theoretical Frank-Kasper  phase peak positions. Thus, these results indicate the formation of a Frank-Kasper  phase in the PB-PCL/PB blend at 140 °C...
March 24, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/28337411/physiological-and-pathological-high-frequency-oscillations-have-distinct-sleep-homeostatic-properties
#7
Nicolás von Ellenrieder, François Dubeau, Jean Gotman, Birgit Frauscher
OBJECTIVE: The stage of sleep is a known modulator of high-frequency oscillations (HFOs). For instance, high amplitude slow waves during NREM sleep and the subtypes of REM sleep were shown to contribute to a better separation between physiological and pathological HFOs. This study investigated rates and spatial spread of the different HFO types (physiological and pathological ripples in the 80-250 Hz frequency band, and fast ripples above 250 Hz) depending on time spent in sleep across the different sleep cycles...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28334469/stereoisomerism-of-bis-sigma-zincane-complexes-evidence-for-an-intramolecular-pathway
#8
Mark Richard Crimmin, Olga Ekkert, Andrew White
The first bis(sigma-zincane) complexes, heterotrimetallic species [M(CO)4(2-HZnBDI)2], have been prepared (BDI = 2-{2,6-i-Pr2C6H3NCMe}2CH). For M = Cr a single stereoisomer is observed in solution and the solid-state. For M = Mo and W, cis and trans isomers where found to reversibly interconvert at 297 K. Despite the huge steric demands of the ligand on zinc, in all cases the cis isomer was found to be the most thermodynamically stable. The activation parameters for the isomerization when M = Mo are H‡ = 20...
March 23, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28334060/bone-repair-process-in-defects-of-diabetic-rats-filled-with-autogenous-bone-graft-and-covered-with-homogenous-bone-matrix-membrane-or-polytetrafluoroethylene-membrane
#9
Carlos Alberto Timóteo, Alessandra Marcondes Aranega, Elio Hitoshi Shinohara, Juliana Zorzi Coléte
PURPOSE: To analyze the process of repair of bone defects in diabetic rats filled with autogenous bone and covered with membranes of homogenous bone matrix or expanded polytetrafluoroethylene (ePTFE). MATERIALS AND METHODS: One hundred twenty male rats were divided into two groups: group 1 (IC), without systemic alterations (control), received an intravenous injection of citrate buffer at 0.01 M, pH 4.5; group 2 (IID) (diabetic) received an intravenous injection of streptozotocin (Sigma-Aldrich) dissolved in 0...
March 23, 2017: International Journal of Oral & Maxillofacial Implants
https://www.readbyqxmd.com/read/28333276/genetic-evidence-that-multiple-proteases-are-involved-in-modulation-of-heat-induced-activation-of-the-sigma-factor-sigi-in-bacillus-subtilis
#10
Tai-Yen Liu, Shu-Hung Chu, Yi-Nei Hu, Jyun-Jhih Wang, Gwo-Chyuan Shaw
The Bacillus subtilis sigI-rsgI operon encodes the heat-inducible sigma factor SigI and its cognate anti-sigma factor RsgI. The heat-activated SigI positively regulates expression of sigI itself and genes involved in cell wall homeostasis and heat resistance. It remains unknown which protease(s) may contribute to degradation of RsgI and heat-induced activation of SigI. In this study, we found that transcription of sigI from its σI-dependent promoter under heat stress was downregulated in a strain lacking the heat-inducible sigma factor SigB...
March 8, 2017: FEMS Microbiology Letters
https://www.readbyqxmd.com/read/28325763/pseudomonas-aeruginosa-alginate-overproduction-promotes-coexistence-with-staphylococcus-aureus-in-a-model-of-cystic-fibrosis-respiratory-infection
#11
Dominique H Limoli, Gregory B Whitfield, Tomoe Kitao, Melissa L Ivey, Michael R Davis, Nora Grahl, Deborah A Hogan, Laurence G Rahme, P Lynne Howell, George A O'Toole, Joanna B Goldberg
While complex intra- and interspecies microbial community dynamics are apparent during chronic infections and likely alter patient health outcomes, our understanding of these interactions is currently limited. For example, Pseudomonas aeruginosa and Staphylococcus aureus are often found to coinfect the lungs of patients with cystic fibrosis (CF), yet these organisms compete under laboratory conditions. Recent observations that coinfection correlates with decreased health outcomes necessitate we develop a greater understanding of these interbacterial interactions...
March 21, 2017: MBio
https://www.readbyqxmd.com/read/28324201/potential-roles-of-mitochondria-associated-er-membranes-mams-in-traumatic-brain-injury
#12
REVIEW
Dongdong Sun, Xin Chen, Gang Gu, Jianhao Wang, Jianning Zhang
The endoplasmic reticulum (ER) and mitochondria have both been shown to be critical in cellular homeostasis. The functions of the ER and mitochondria are independent but interrelated. These two organelles could form physical interactions, known as MAMs, to regulate physiological functions between ER and mitochondria to maintain Ca(2+), lipid, and metabolite exchange. Several proteins are located in MAMs, including RNA-dependent protein kinase (PKR)-like ER kinase, inositol 1,4,5-trisphosphate receptors, phosphofurin acidic cluster sorting protein-2 and sigma-1 receptor to ensure regulation...
March 21, 2017: Cellular and Molecular Neurobiology
https://www.readbyqxmd.com/read/28322757/impaired-clinical-utility-of-sequential-patient-gem-blood-gas-measurements-associated-with-calibration-schedule
#13
George S Cembrowski, Qian Xu, Adam R Cembrowski, Junyi Mei, Hossein Sadrzadeh
BACKGROUND: Within- and/or between-instrument variation may falsely indicate patient trends or obscure real trends. We employ a methodology that transforms sequential intra-patient results into estimates of biologic and analytic variation. We previously derived realistic biologic variation (sb) of blood gas (BG) and hematology analytes. We extend this methodology to derive the imprecision of two GEM 4000 BG analyzers. METHODS: A laboratory data repository provided arterial BG, electrolyte and metabolite results generated by two GEM 4000s on ICU patients in 2012-2013...
March 18, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28320883/the-pseudomonas-aeruginosa-two-component-regulator-algr-directly-activates-rsma-expression-in-a-phosphorylation-independent-manner
#14
Sean D Stacey, Danielle A Williams, Christopher L Pritchett
Pseudomonas aeruginosa is an important pathogen of the immunocompromised, causing both acute and chronic infections. In cystic fibrosis (CF) patients, P. aeruginosa causes chronic disease. The impressive sensory network of P. aeruginosa allows the bacteria to sense and respond to a variety of stimuli found in diverse environments. Transcriptional regulators, including alternative sigma factors and response regulators, integrate signals changing gene expression allowing P. aeruginosa to cause infection. The two-component transcriptional regulator AlgR is important in P...
March 20, 2017: Journal of Bacteriology
https://www.readbyqxmd.com/read/28320877/functional-analysis-of-the-alternative-sigma-28-factor-flia-and-its-anti-sigma-factor-flgm-of-the-non-flagellated-legionella-species-l-oakridgensis
#15
Hana Tlapák, Kerstin Rydzewski, Tino Schulz, Dennis Weschka, Eva Schunder, Klaus Heuner
Legionella oakridgensis is causing the Legionnaires' disease but is known to be less virulent than Legionella pneumophilaL. oakridgensis is one of the Legionella species that is non-flagellated. The genes of the flagellar regulon are absent; except the alternative sigma-28 factor (FliA) and its anti-sigma-28 factor (FlgM). Similar to L. oakridgensis, Legionella adelaidensis and Legionella londiniensis, located in the same phylogenetic clade, they have no flagellar regulon, although both are positive for fliA and flgM Herein, we investigated the role and function of both genes to better understand the role of FliA, the positive regulator of flagellin expression, in non-flagellated strains...
March 20, 2017: Journal of Bacteriology
https://www.readbyqxmd.com/read/28320837/the-suf-iron-sulfur-cluster-biosynthetic-system-is-essential-in-staphylococcus-aureus-and-decreased-suf-function-results-in-global-metabolic-defects-and-reduced-survival-in-human-neutrophils
#16
Christina A Roberts, Hassan M Al-Tameemi, Ameya A Mashruwala, Zuelay Rosario-Cruz, Unnati Chauhan, William E Sause, Victor J Torres, William J Belden, Jeffrey M Boyd
Staphylococcus aureus remains a causative agent for morbidity and mortality worldwide. This is, in part, a result of antimicrobial resistance highlighting the need to uncover novel antibiotic targets and discover new therapeutic agents. In the present study we explored the possibility that iron-sulfur (Fe-S) cluster synthesis is a viable antimicrobial target. RNA interference studies established that Suf (sulfur mobilization) dependent Fe-S cluster synthesis is essential in S. aureus We found that sufCDSUB were cotranscribed and suf transcription was positively influenced by sigma factor B...
March 20, 2017: Infection and Immunity
https://www.readbyqxmd.com/read/28320584/growth-charts-for-brazilian-children-with-down-syndrome-birth-to-20-years-of-age
#17
Fabio Bertapelli, Stamatis Agiovlasitis, Maira Rossmann Machado, Raísa do Val Roso, Gil Guerra-Junior
BACKGROUND: The growth of youth with Down syndrome (DS) differs from that of youth without DS, and growth charts specific to DS have been developed. However, little is known about the growth of Brazilian youth with DS. The objective of this study was to construct growth charts for Brazilian youth with DS and compare the growth data with the Child Growth Standards of the World Health Organization (WHO) and charts for children with DS from other studies. METHODS: Mixed longitudinal and cross-sectional data were collected at University of Campinas, 48 specialized centers for people with intellectual disabilities, and two foundations for people with DS between 2012 and 2015...
March 17, 2017: Journal of Epidemiology
https://www.readbyqxmd.com/read/28320314/quorum-sensing-of-streptococcus-mutans-is-activated-by-aggregatibacter-actinomycetemcomitans-and-by-the-periodontal-microbiome
#18
Szymon P Szafrański, Zhi-Luo Deng, Jürgen Tomasch, Michael Jarek, Sabin Bhuju, Manfred Rohde, Helena Sztajer, Irene Wagner-Döbler
BACKGROUND: The oral cavity is inhabited by complex microbial communities forming biofilms that can cause caries and periodontitis. Cell-cell communication might play an important role in modulating the physiologies of individual species, but evidence so far is limited. RESULTS: Here we demonstrate that a pathogen of the oral cavity, Aggregatibacter actinomycetemcomitans (A. act.), triggers expression of the quorum sensing (QS) regulon of Streptococcus mutans, a well-studied model organism for cariogenic streptococci, in dual-species biofilms grown on artificial saliva...
March 20, 2017: BMC Genomics
https://www.readbyqxmd.com/read/28320023/-update-opipramol
#19
Maximilian Gahr, Christoph Hiemke, Bernhard J Connemann
Opipramol was developed in the 1960s as an antidepressant and has chemical similarities with tricyclic antidepressants. Pharmacodynamic properties with absent reuptake inhibition of serotonin and noradrenaline and agonism at sigma receptors distinguish opipramol from tricyclics. Furthermore, antidepressive effects are smaller than the anxiolytic ones. The mechanism of action of opipramol is currently not sufficiently understood. Agonistic effects at sigma receptors have been linked with therapeutic effects...
March 2017: Fortschritte der Neurologie-Psychiatrie
https://www.readbyqxmd.com/read/28319371/expression-of-heterologous-sigma-factor-expands-the-searchable-space-for-biofuel-tolerance-mechanisms
#20
Timothy A Tomko, Mary J Dunlop
Microorganisms can produce hydrocarbons that can serve as replacements or additions to conventional liquid fuels for use in the transportation sector. However, a common problem in the microbial synthesis of biofuels is that these compounds often have toxic effects on the cell. In this study, we focused on mitigating the toxicity of the bio-jet fuel precursor pinene on Escherichia coli. We used genomic DNA from Pseudomonas putida KT2440, which has innate solvent-tolerance properties, to create transgenic libraries in an E...
March 20, 2017: ACS Synthetic Biology
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