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https://www.readbyqxmd.com/read/29040869/accessing-the-long-time-limit-in-diffusion-nmr-the-case-of-singlet-assisted-diffusive-diffraction-q-space
#1
Giuseppe Pileio, Sylwia Ostrowska
The latest developments in the field of long-lived spin states are merged with pulsed-field gradient techniques to extend the diffusion time beyond what is currently achievable in standard q-space diffusive-diffraction studies. The method uses nearly-equivalent spin-1/2 pairs that let diffusion times of the order of many minutes to be measured allowing access to the long-time limit in cavities of macroscopic size (millimeters). A pulse sequence suitable to exploit this regime has been developed and validated with the use of numerical simulations and experiments...
October 9, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/29036991/-molecular-epidemiology-of-carbapenem-resistant-klebsiella-pneumoniae-in-a-hospital-in-beijing
#2
D K Chen, H J Zhou
Objective: To reveal the molecular epidemiological characteristics of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) isolated from a three level teaching hospital in Beijing. Methods: Pulsed field gel electrophoresis (PFGE) was carried out to subtyping 375 CRKP isolated in that hospital between May 2010 and October 2015. Fifteen strains were chose based on the PFGE patterns to be analyzed by multi-locus sequence typing (MLST) and detection of carbapenem-resistance genes. One strain (A1502) was selected for whole genome sequencing and analyzing...
October 6, 2017: Zhonghua Yu Fang Yi Xue za Zhi [Chinese Journal of Preventive Medicine]
https://www.readbyqxmd.com/read/29035987/low-intensity-pulsed-ultrasound-for-early-stage-lumbar-spondylolysis-in-young-athletes
#3
Masahiro Tsukada, Toshiro Takiuchi, Kota Watanabe
OBJECTIVE: To examine the effect of low-intensity pulsed ultrasound (LIPUS) on early-stage spondylolysis in young athletes. DESIGN: Case-control study. SETTING: A single outpatient orthopedic and sports clinic. PATIENTS: A total of 82 young athletes (80 boys and 2 girls; mean age, 14.8 years; range, 10-18 years) with early-stage lumbar spondylolysis were enrolled in this study. All patients were examined by plain radiography and magnetic resonance imaging...
October 10, 2017: Clinical Journal of Sport Medicine: Official Journal of the Canadian Academy of Sport Medicine
https://www.readbyqxmd.com/read/29034124/multi-provincial-salmonellosis-outbreak-related-to-newly-hatched-chicks-and-poults-a-genomics-perspective
#4
Matthew A Croxen, Kimberley A Macdonald, Matthew Walker, Nancy deWith, Erin Zabek, Christy Peterson, Aleisha Reimer, Linda Chui, Lorelee Tschetter, Linda Hoang, Robin K King
BACKGROUND: A multi-provincial outbreak of Salmonella enterica serovar Enteritidis was linked to newly hatched chicks and poults from a single hatchery during the spring of 2015. In total, there were 61 human cases that were epidemiologically confirmed to be linked to the chicks and poults and the outbreak was deemed to have ended in the summer of 2015. METHODS: PulseNet Canada, in coordination with the affected provinces, used genome sequencing of human and agricultural Salmonella Enteritidis isolates to aid in the epidemiological investigation, while also using traditional typing methods such as phagetyping and pulsed-field gel electrophoresis (PFGE)...
August 9, 2017: PLoS Currents
https://www.readbyqxmd.com/read/29032055/microbiological-characterization-of-klebsiella-pneumoniae-isolates-causing-bloodstream-infection-from-five-tertiary-hospitals-in-beijing-china
#5
Yanning Ma, Chunmei Bao, Jie Liu, Xiuhong Hao, Jingui Cao, Liyan Ye, Jiyong Yang
BACKGROUND: Klebsiella pneumoniae exhibits prevalence in China. Little is known about the microbiological characterization of clinical K. pneumoniae isolates causing bloodstream infections (BSIs). METHODS: BSI-causing K. pneumoniae (BSIKpn) isolates were collected from five tertiary-care hospitals in Beijing, China. Their genetic relatedness was analyzed by pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility was determined by agar dilution method, and sequence type (ST) was evaluated by multilocus sequence typing (MLST)...
October 11, 2017: Journal of Global Antimicrobial Resistance
https://www.readbyqxmd.com/read/29030403/new-blood-pressure-associated-loci-identified-in-meta-analyses-of-475%C3%A2-000-individuals
#6
Aldi T Kraja, James P Cook, Helen R Warren, Praveen Surendran, Chunyu Liu, Evangelos Evangelou, Alisa K Manning, Niels Grarup, Fotios Drenos, Xueling Sim, Albert Vernon Smith, Najaf Amin, Alexandra I F Blakemore, Jette Bork-Jensen, Ivan Brandslund, Aliki-Eleni Farmaki, Cristiano Fava, Teresa Ferreira, Karl-Heinz Herzig, Ayush Giri, Franco Giulianini, Megan L Grove, Xiuqing Guo, Sarah E Harris, Christian T Have, Aki S Havulinna, He Zhang, Marit E Jørgensen, AnneMari Käräjämäki, Charles Kooperberg, Allan Linneberg, Louis Little, Yongmei Liu, Lori L Bonnycastle, Yingchang Lu, Reedik Mägi, Anubha Mahajan, Giovanni Malerba, Riccardo E Marioni, Hao Mei, Cristina Menni, Alanna C Morrison, Sandosh Padmanabhan, Walter Palmas, Alaitz Poveda, Rainer Rauramaa, Nigel William Rayner, Muhammad Riaz, Ken Rice, Melissa A Richard, Jennifer A Smith, Lorraine Southam, Alena Stančáková, Kathleen E Stirrups, Vinicius Tragante, Tiinamaija Tuomi, Ioanna Tzoulaki, Tibor V Varga, Stefan Weiss, Andrianos M Yiorkas, Robin Young, Weihua Zhang, Michael R Barnes, Claudia P Cabrera, He Gao, Michael Boehnke, Eric Boerwinkle, John C Chambers, John M Connell, Cramer K Christensen, Rudolf A de Boer, Ian J Deary, George Dedoussis, Panos Deloukas, Anna F Dominiczak, Marcus Dörr, Roby Joehanes, Todd L Edwards, Tõnu Esko, Myriam Fornage, Nora Franceschini, Paul W Franks, Giovanni Gambaro, Leif Groop, Göran Hallmans, Torben Hansen, Caroline Hayward, Oksa Heikki, Erik Ingelsson, Jaakko Tuomilehto, Marjo-Riitta Jarvelin, Sharon L R Kardia, Fredrik Karpe, Jaspal S Kooner, Timo A Lakka, Claudia Langenberg, Lars Lind, Ruth J F Loos, Markku Laakso, Mark I McCarthy, Olle Melander, Karen L Mohlke, Andrew P Morris, Colin N A Palmer, Oluf Pedersen, Ozren Polasek, Neil R Poulter, Michael A Province, Bruce M Psaty, Paul M Ridker, Jerome I Rotter, Igor Rudan, Veikko Salomaa, Nilesh J Samani, Peter J Sever, Tea Skaaby, Jeanette M Stafford, John M Starr, Pim van der Harst, Peter van der Meer, Cornelia M van Duijn, Anne-Claire Vergnaud, Vilmundur Gudnason, Nicholas J Wareham, James G Wilson, Cristen J Willer, Daniel R Witte, Eleftheria Zeggini, Danish Saleheen, Adam S Butterworth, John Danesh, Folkert W Asselbergs, Louise V Wain, Georg B Ehret, Daniel I Chasman, Mark J Caulfield, Paul Elliott, Cecilia M Lindgren, Daniel Levy, Christopher Newton-Cheh, Patricia B Munroe, Joanna M M Howson
BACKGROUND: Genome-wide association studies have recently identified >400 loci that harbor DNA sequence variants that influence blood pressure (BP). Our earlier studies identified and validated 56 single nucleotide variants (SNVs) associated with BP from meta-analyses of exome chip genotype data. An additional 100 variants yielded suggestive evidence of association. METHODS AND RESULTS: Here, we augment the sample with 140 886 European individuals from the UK Biobank, in whom 77 of the 100 suggestive SNVs were available for association analysis with systolic BP or diastolic BP or pulse pressure...
October 2017: Circulation. Cardiovascular Genetics
https://www.readbyqxmd.com/read/29029832/tumour-auto-contouring-on-2d-cine-mri-for-locally-advanced-lung-cancer-a-comparative-study
#7
Martin F Fast, Björn Eiben, Martin J Menten, Andreas Wetscherek, David J Hawkes, Jamie R McClelland, Uwe Oelfke
BACKGROUND AND PURPOSE: Radiotherapy guidance based on magnetic resonance imaging (MRI) is currently becoming a clinical reality. Fast 2d cine MRI sequences are expected to increase the precision of radiation delivery by facilitating tumour delineation during treatment. This study compares four auto-contouring algorithms for the task of delineating the primary tumour in six locally advanced (LA) lung cancer patients. MATERIAL AND METHODS: Twenty-two cine MRI sequences were acquired using either a balanced steady-state free precession or a spoiled gradient echo imaging technique...
October 10, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/29028543/a-pulse-programmable-parahydrogen-polarizer-using-a-tunable-electromagnet-and-dual-channel-nmr-spectrometer
#8
Aaron M Coffey, Roman V Shchepin, Bibo Feng, Raul D Colon, Ken Wilkens, Kevin W Waddell, Eduard Y Chekmenev
Applications of parahydrogen induced polarization (PHIP) often warrant conversion of the chemically-synthesized singlet-state spin order into net heteronuclear magnetization. In order to obtain optimal yields from the overall hyperpolarization process, catalytic hydrogenation must be tightly synchronized to subsequent radiofrequency (RF) transformations of spin order. Commercial NMR consoles are designed to synchronize applied waves on multiple channels and consequently are well-suited as controllers for these types of hyperpolarization experiments that require tight coordination of RF and non-RF events...
September 30, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/29027556/effect-of-a-heavy-heteroatom-on-triplet-formation-and-interactions-in-single-conjugated-polymer-molecules-and-aggregates
#9
Benjamin D Datko, Alan K Thomas, Zhuping Fei, Martin Heeney, John K Grey
Triplet formation and interactions with emissive singlet excitons are investigated in poly(3-hexylselenophene) (P3HS) using single molecule spectroscopy. P3HS is a heavy atom analog of the more commonly studied poly(3-hexylthiophene) (P3HT), a benchmark polymer for solar cells. P3HS tends to aggregate strongly which necessitates dilution to ultra-low levels within a solid inert host in order to resolve photophysical responses of single chains. Fluorescence excitation intensity modulation is performed on isolated P3HS chains using a sequence of rectangular pulses of varying intensities to probe the presence of spin-forbidden triplet excitons...
October 13, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29026633/the-first-fatal-case-of-corynebacterium-ulcerans-infection-in-japan
#10
Ken Otsuji, Kazumasa Fukuda, Takeru Endo, Satoko Shimizu, Nobuya Harayama, Midori Ogawa, Akihiko Yamamoto, Kaoru Umeda, Toshiyuki Umata, Hiroyuki Seki, Masaaki Iwaki, Masayuki Kamochi, Mitsumasa Saito
Introduction.Corynebacterium ulcerans (C. ulcerans) is a zoonotic pathogen that occasionally causes diphtheria-like symptoms in humans. Cases of C. ulcerans infection have been increasing in recent years, and C. ulcerans has been recognized as an emerging pathogen. Case presentation. Here we report a case of asphyxia death due to pseudomembrane caused by diphtheria toxin (DT)-producing C. ulcerans. This is, to our knowledge, the first fatal case of C. ulcerans infection in Japan. A strain of C. ulcerans was obtained from the patient's pet cat and was confirmed to be identical to the patient's isolate by sequencing of the 16S rRNA gene and the DT gene, by pulsed-field gel electrophoresis (PFGE) and by ribotyping...
August 2017: JMM Case Reports
https://www.readbyqxmd.com/read/29024712/brief-activation-of-gabaergic-interneurons-initiates-the-transition-to-ictal-events-through-post-inhibitory-rebound-excitation
#11
Michael Chang, Joshua A Dian, Suzie Dufour, Lihua Wang, Homeira Moradi-Chameh, Meera Ramani, Liang Zhang, Peter L Carlen, Thilo Womelsdorf, Taufik A Valiante
Activation of γ-aminobutyric acid (GABAA) receptors have been associated with the onset of epileptiform events. To investigate if a causal relationship exists between GABAA receptor activation and ictal event onset, we activated inhibitory GABAergic networks in the superficial layer (2/3) of the somatosensory cortex during hyperexcitable conditions using optogenetic techniques in mice expressing channelrhodopsin-2 in all GABAergic interneurons. We found that a brief 30ms light pulse reliably triggered either an interictal-like event (IIE) or ictal-like ("ictal") event in the in vitro cortical 4-Aminopyridine (4-AP) slice model...
October 9, 2017: Neurobiology of Disease
https://www.readbyqxmd.com/read/29020115/genetic-characteristics-and-molecular-epidemiology-of-vancomycin-resistant-enterococci-isolates-from-caribbean-countries
#12
Patrick Eberechi Akpaka, Shivnarine Kissoon, Padman Jayaratne, Clyde Wilson, George R Golding, Alison M Nicholson, Delores B Lewis, Sandra M Hermelijn, Alexis Wilson-Pearson, Ashley Smith
Emergence of vancomycin-resistant Enterococci (VRE) that first appeared on the stage about three decades ago is now a major concern worldwide as it has globally reached every continent. Our aim was to simply undertake a multinational study to delineate the resistance and virulence genes of clinical isolates of VRE isolates from the Caribbean. We employed both conventional (standard microbiological methods including use of E-test strips, chromogenic agar) and molecular methods (polymerase chain reactions-PCR, pulsed-field gel electrophoresis-PFGE and multilocus sequence typing-MLST) to analyze and characterize 245 Enterococci species and 77 VRE isolates from twelve hospitals from eight countries in the Caribbean...
2017: PloS One
https://www.readbyqxmd.com/read/29018890/-magnetic-resonance-imaging-findings-after-shoulder-surgery-what-the-radiologist-needs-to-know
#13
REVIEW
U L Fahlenkamp, C Gerhardt, K-G A Hermann
Even primary diagnostic evaluation of the shoulder is a challenge for radiologists. Many imaging findings that definitely indicate abnormal findings in the untreated shoulder should be evaluated carefully in postoperative patients. Artifacts caused by implants or metal abrasion pose considerable problems in postoperative magnetic resonance imaging (MRI). Classic approaches to minimizing artifacts caused by foreign bodies include using turbo spin echo sequences, increasing bandwidth, and reducing voxel size...
October 10, 2017: Der Radiologe
https://www.readbyqxmd.com/read/29018631/multi-parameter-ensemble-learning-for-automated-vertebral-body-segmentation-in-heterogeneously-acquired-clinical-mr-images
#14
Bilwaj Gaonkar, Yihao Xia, Diane S Villaroman, Allison Ko, Mark Attiah, Joel S Beckett, Luke Macyszyn
The development of quantitative imaging biomarkers in medicine requires automatic delineation of relevant anatomical structures using available imaging data. However, this task is complicated in clinical medicine due to the variation in scanning parameters and protocols, even within a single medical center. Existing literature on automatic image segmentation using MR data is based on the analysis of highly homogenous images obtained using a fixed set of pulse sequence parameters (TR/TE). Unfortunately, algorithms that operate on fixed scanning parameters do not avail themselves to real-world daily clinical use due to the existing variation in scanning parameters and protocols...
2017: IEEE Journal of Translational Engineering in Health and Medicine
https://www.readbyqxmd.com/read/29017930/cardiac-magnetic-resonance-imaging-using-wideband-sequences-in-patients-with-non-conditional-cardiac-implanted-electronic-devices
#15
Duc H Do, Vaughn Eyvazian, Aileen J Bayoneta, Peng Hu, J Paul Finn, Jason S Bradfield, Kalyanam Shivkumar, Noel G Boyle
BACKGROUND: Magnetic resonance imaging (MRI) has been performed safely in patients without MRI-conditional cardiac implantable electronic devices (CIED), but experience specifically with cardiac magnetic resonance imaging (CMR) is limited in this patient population. OBJECTIVE: Evaluate the safety of CMR in non-MRI-conditional CIED and the interpretability of images using wideband sequences. METHODS: We performed 114 consecutive CMR studies in 111 patients (mean age 59±14 years with 12 pacemakers, 73 implantable cardioverter defibrillators, 29 biventricular defibrillators) utilizing a wideband pulse sequence for late gadolinium enhancement (LGE) imaging...
October 7, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/28993232/mr-elastography-of-the-brain-and-its-application-in-neurological-diseases
#16
REVIEW
Matthew C Murphy, John Huston, Richard L Ehman
Magnetic resonance elastography (MRE) is an imaging technique for noninvasively and quantitatively assessing tissue stiffness, akin to palpation. MRE is further able assess the mechanical properties of tissues that cannot be reached by hand including the brain. The technique is a three-step process beginning with the introduction of shear waves into the tissue of interest by applying an external vibration. Next, the resulting motion is imaged using a phase-contrast MR pulse sequence with motion encoding gradients that are synchronized to the vibration...
October 6, 2017: NeuroImage
https://www.readbyqxmd.com/read/28990406/in-vivo-application-of-proton-electron-double-resonance-imaging
#17
Shun Kishimoto, Murali K Cherukuri, Valery V Khramtsov, Hideo Utsumi, David J Lurie
SIGNIFICANCE: Proton-electron double resonance imaging (PEDRI) employs electron paramagnetic resonance irradiation with low field magnetic resonance imaging (MRI) so that the electron spin polarization is transferred to nearby protons, resulting in higher signal. PEDRI provides information about free radical distribution and, indirectly, about the local microenvironment such as pO2, tissue permeability, redox status, and acid-base balance. Recent Advances: Local acid-base balance can be imaged by exploiting the different resonance frequency of radical probes between R and RH+ forms...
October 7, 2017: Antioxidants & Redox Signaling
https://www.readbyqxmd.com/read/28985137/principles-of-quantitative-mr-imaging-with-illustrated-review-of-applicable-modular-pulse-diagrams
#18
Andrew F Mills, Osamu Sakai, Stephan W Anderson, Hernan Jara
Continued improvements in diagnostic accuracy using magnetic resonance (MR) imaging will require development of methods for tissue analysis that complement traditional qualitative MR imaging studies. Quantitative MR imaging is based on measurement and interpretation of tissue-specific parameters independent of experimental design, compared with qualitative MR imaging, which relies on interpretation of tissue contrast that results from experimental pulse sequence parameters. Quantitative MR imaging represents a natural next step in the evolution of MR imaging practice, since quantitative MR imaging data can be acquired using currently available qualitative imaging pulse sequences without modifications to imaging equipment...
October 6, 2017: Radiographics: a Review Publication of the Radiological Society of North America, Inc
https://www.readbyqxmd.com/read/28983745/physical-and-chemical-enhancement-of-and-adaptive-resistance-to-irreversible-electroporation-of-pancreatic-cancer
#19
Qi Shao, Feng Liu, Connie Chung, Kianna Elahi-Gedwillo, Paolo P Provenzano, Bruce Forsyth, John C Bischof
Irreversible electroporation (IRE) can be used to treat cancer by electrical pulses, with advantages over traditional thermal approaches. Here we assess for the first time the IRE response of pancreatic cancer, one of the deadliest forms of cancer, both in vitro and in vivo. We demonstrate that both established and primary cancer cell lines can be destroyed by IRE, but with differential susceptibility and thresholds. We further demonstrate in vitro that viability for a given IRE dose can vary with the local chemistry as outcomes were shown to depend on suspending medium and reduction of glucose in the media significantly improved IRE destruction...
October 5, 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/28981438/filtering-of-ecg-signals-distorted-by-magnetic-field-gradients-during-mri-using-non-linear-filters-and-higher-order-statistics
#20
Marcus Schmidt, Johannes W Krug, Michael N Rosenheimer, Georg Rose
The electrocardiogram (ECG) is the state-of-the-art signal for patient monitoring and gating in cardiovascular magnetic resonance (CMR) imaging applications. However, ECG signals are severely distorted during MRI scans due to the effects of static magnetic fields, radio frequency pulses and fast-switching gradient magnetic fields. Gradient-induced artifacts that cause high frequency peaks in the ECG signal especially hamper a correct and reliable QRS detection. To cope with this problem, a new median-based real-time gradient filter (M1) approach was developed...
June 5, 2017: Biomedizinische Technik. Biomedical Engineering
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