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https://www.readbyqxmd.com/read/29779192/impact-of-weak-water-deficit-on-growth-photosynthetic-primary-processes-and-storage-processes-in-pine-and-spruce-seedlings
#1
Ilya E Zlobin, Yury V Ivanov, Alexander V Kartashov, Boris A Sarvin, Andrey N Stavrianidi, Vladimir D Kreslavski, Vladimir V Kuznetsov
We investigated the influence of 40 days of drought on growth, storage processes and primary photosynthetic processes in 3-month-old Scots pine and Norway spruce seedlings growing in perlite culture. Water stress significantly affected seedling water status, whereas absolute dry biomass growth was not substantially influenced. Water stress induced an increase in non-structural carbohydrate content (sugars, sugar alcohols, starch) in the aboveground part of pine seedlings in contrast to spruce seedlings. Due to the relatively low content of sugars and sugar alcohols in seedling organs, their expected contribution to osmotic potential changes was quite low...
May 19, 2018: Photosynthesis Research
https://www.readbyqxmd.com/read/29778549/linked-color-imaging-can-help-gastric-helicobacter-pylori-infection-diagnosis-during-endoscopy
#2
Tsung-Hsing Chen, Chen-Ming Hsu, Hao-Tsai Cheng, Yin-Yi Chu, Ming-Yao Su, Jun-Te Hsu, Ta-Sen Yeh, Chang-Fu Kuo, Cheng-Tang Chiu
BACKGROUND: Esophagogastroduodenoscopy (EGD) is a standard tool for detection of mucosal and submucosal lesions. However, identification of Helicobacter pylori (H. P) infection using EGD alone is limited in accuracy. Linked color imaging (LCI) is a novel tool to capture real-time image with sufficient contrast to observe mucosal microstructure. METHODS: This study aims to evaluate the applicability of LCI in the identification of H. pylori infection. Consecutive 122 patients scheduled for EGD were included...
May 16, 2018: Journal of the Chinese Medical Association: JCMA
https://www.readbyqxmd.com/read/29778495/protection-of-photosynthesis-in-desiccation-tolerant-resurrection-plants
#3
Dinakar Challabathula, Qingwei Zhang, Dorothea Bartels
Inhibition of photosynthesis is a central, primary response that is observed in both desiccation-tolerant and desiccation-sensitive plants affected by drought stress. Decreased photosynthesis during drought stress can either be due to the limitation of carbon dioxide entry through the stomata and the mesophyll cells, due to increased oxidative stress or due to decreased activity of photosynthetic enzymes. Although the photosynthetic rates decrease in both desiccation-tolerant and sensitive plants during drought, the remarkable difference lies in the complete recovery of photosynthesis after rehydration in desiccation-tolerant plants...
May 12, 2018: Journal of Plant Physiology
https://www.readbyqxmd.com/read/29777983/young-infants-discrimination-of-subtle-phonetic-contrasts
#4
Megha Sundara, Céline Ngon, Katrin Skoruppa, Naomi H Feldman, Glenda Molina Onario, James L Morgan, Sharon Peperkamp
It is generally accepted that infants initially discriminate native and non-native contrasts and that perceptual reorganization within the first year of life results in decreased discrimination of non-native contrasts, and improved discrimination of native contrasts. However, recent findings from Narayan, Werker, and Beddor (2010) surprisingly suggested that some acoustically subtle native-language contrasts might not be discriminated until the end of the first year of life. We first provide countervailing evidence that young English-learning infants can discriminate the Filipino contrast tested by Narayan et al...
May 16, 2018: Cognition
https://www.readbyqxmd.com/read/29777820/accuracy-and-precision-of-quantitative-dce-mri-parameters-how-should-one-estimate-contrast-concentration
#5
Nicole Wake, Hersh Chandarana, Henry Rusinek, Koji Fujimoto, Linda Moy, Daniel K Sodickson, Sungheon Gene Kim
INTRODUCTION: Pharmacokinetic parameters derived from dynamic contrast-enhanced MRI (DCE-MRI) data are sensitive to acquisition and post-processing techniques, which makes it difficult to compare results obtained using different methods. In particular, one of the most important factors affecting estimation of model parameters is how to convert MRI signal intensities to contrast agent concentration. The purpose of our study was to quantitatively compare a linear signal-to-concentration conversion (LC) as an approximation and a non-linear conversion (NLC) based on the MRI signal equation, in terms of the accuracy and precision of the pharmacokinetic parameters in T1 -weighted DCE-MRI...
May 16, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29777724/novel-mirna-biomarkers-for-genotoxicity-screening-in-mouse
#6
Hiroyuki Oka, Koichi Masuno, Takeki Uehara, Toru Okamoto, Yoshiharu Matsuura, Toru Nakano, Shinpei Yamaguchi
The genotoxic potential of drugs is a serious problem, and its evaluation is one of the most critical processes of drug development. Although the comet assay of compound-exposed tissue is a frequently used genotoxicity test, its high false-positive rate is a major complication, and we consistently obtained false-positive results using the comet assay of mouse liver for nine hepatotoxic non-genotoxins (NGTXs). To identify novel genotoxin (GTX)-specific biomarkers, we screened the expression of 750 microRNAs (miRNAs) in the livers of mice treated with GTXs or NGTXs...
May 16, 2018: Toxicology
https://www.readbyqxmd.com/read/29777330/down-regulating-il-6-gp130-targets-improved-the-anti-tumor-effects-of-5-fluorouracil-in-colon-cancer
#7
Sanhong Li, Jilai Tian, Hongming Zhang, Shoubing Zhou, Xiyong Wang, Lei Zhang, Jiapeng Yang, Zhigang Zhang, Zhenling Ji
Recent studies have confirmed that IL-6/GP130 targets are closely associated with tumor growth, metastasis and drug resistance. 5-Fluorouracil (5-FU) is the most common chemotherapeutic agent for colon cancer but is limited due to chemoresistance and high cytotoxicity. Bazedoxifene (BZA), a third-generation selective estrogen receptor modulator, was discovered by multiple ligand simultaneous docking and drug repositioning approaches to have a novel function as an IL-6/GP130 target inhibitor. Thus, we speculated that in colon cancer, the anti-tumor efficacy of 5-FU might be increased in combination with IL-6/GP130 inhibitors...
May 18, 2018: Apoptosis: An International Journal on Programmed Cell Death
https://www.readbyqxmd.com/read/29776600/contrast-enhanced-ultrasound-quantifies-the-perfusion-within-tibial-non-unions-and-predicts-the-outcome-of-revision-surgery
#8
Daniel Krammer, Gerhard Schmidmaier, Marc-André Weber, Julian Doll, Christoph Rehnitz, Christian Fischer
Vascularity is one of the factors determining successful bone regeneration. This prospective study focused on quantifying the microperfusion of tibial non-unions with contrast-enhanced ultrasound (CEUS) 12 wk after revision surgery and comparing it with the osseous consolidation at a maximum of 24 mo assessed with standard radiography and computed tomography. Of 36 patients with tibial non-unions, 28 (77.8%) manifested consolidation, and 8 patients required further revision surgery. CEUS revealed significantly higher perfusion in consolidated versus persistent non-unions for all quantification parameters (e...
May 15, 2018: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/29776484/corticotropin-releasing-factor-in-the-brain-and-blocking-spinal-descending-signals-induce-hyperalgesia-in-the-latent-sensitization-model-of-chronic-pain
#9
Wenling Chen, Yvette Taché, Juan Carlos Marvizón
Latent sensitization is a model of chronic pain in which an injury triggers a period of hyperalgesia followed by an apparent recovery, but in which pain sensitization persists but is suppressed by opioid and adrenergic receptors. One important characteristic of latent sensitization is that hyperalgesia can be triggered by acute stress. To determine whether the effect of stress is mimicked by the activation of corticotropin-releasing factor (CRF) signaling in the brain, rats with latent sensitization induced by injecting complete Freund's adjuvant (CFA, 50 μl) in one hind paw were given an intracerebroventricular (i...
June 15, 2018: Neuroscience
https://www.readbyqxmd.com/read/29776394/influence-of-blinding-on-treatment-effect-size-estimate-in-randomized-controlled-trials-of-oral-health-interventions
#10
Humam Saltaji, Susan Armijo-Olivo, Greta G Cummings, Maryam Amin, Bruno R da Costa, Carlos Flores-Mir
BACKGROUND: Recent methodologic evidence suggests that lack of blinding in randomized trials can result in under- or overestimation of the treatment effect size. The objective of this study is to quantify the extent of bias associated with blinding in randomized controlled trials of oral health interventions. METHODS: We selected all oral health meta-analyses that included a minimum of five randomized controlled trials. We extracted data, in duplicate, related to nine blinding-related criteria, namely: patient blinding, assessor blinding, care-provider blinding, investigator blinding, statistician blinding, blinding of both patients and assessors, study described as "double blind", blinding of patients, assessors, and care providers concurrently, and the appropriateness of blinding...
May 18, 2018: BMC Medical Research Methodology
https://www.readbyqxmd.com/read/29776378/differential-induction-of-mutant-sod1-misfolding-and-aggregation-by-tau-and-%C3%AE-synuclein-pathology
#11
Michael C Pace, Guilian Xu, Susan Fromholt, John Howard, Benoit I Giasson, Jada Lewis, David R Borchelt
BACKGROUND: Prior studies in C. elegans demonstrated that the expression of aggregation-prone polyglutamine proteins in muscle wall cells compromised the folding of co-expressed temperature-sensitive proteins, prompting interest in whether the accumulation of a misfolded protein in pathologic features of human neurodegenerative disease burdens cellular proteostatic machinery in a manner that impairs the folding of other cellular proteins. METHODS: Mice expressing high levels of mutant forms of tau and α-synuclein (αSyn), which develop inclusion pathologies of the mutant protein in brain and spinal cord, were crossed to mice expressing low levels of mutant superoxide dismutase 1 fused to yellow fluorescent protein (G85R-SOD1:YFP) for aging and neuropathological evaluation...
May 18, 2018: Molecular Neurodegeneration
https://www.readbyqxmd.com/read/29775791/an-imaging-biomarker-for-assessing-hepatic-function-in-patients-with-primary-sclerosing-cholangitis
#12
Jennifer Schulze, Henrike Lenzen, Jan B Hinrichs, Burckhardt Ringe, Michael P Manns, Frank Wacker, Kristina I Ringe
BACKGROUND & AIMS: We aimed to evaluate the potential of hepatobiliary phase magnetic resonance imaging (MRI) as parameter for assessment of hepatocellular function in patients with primary sclerosing cholangitis (PSC). METHODS: We collected data from 111 patients (83 male, 28 female; median, 44 years old), from March 2012 through March 2016, with a confirmed diagnosis of PSC who underwent MRI evaluation before and after injection (hepatobiliary phase) of a hepatocyte-specific contrast agent (gadoxetate disodium)...
May 15, 2018: Clinical Gastroenterology and Hepatology
https://www.readbyqxmd.com/read/29774899/smartphone-based-rapid-quantification-of-viable-bacteria-by-single-cell-microdroplet-turbidity-imaging
#13
Xiaonan Cui, Lihui Ren, Yufei Shan, Xixian Wang, Zhenlong Yang, Chunyu Li, Jian Xu, Bo Ma
Standard plate count (SPC) has been recognized as the golden standard for the quantification of viable bacteria. However, SPC usually takes one to several days to grow individual cells into a visible colony, which greatly hampers its application in rapid bacteria enumeration. Here we present a microdroplet turbidity imaging based digital standard plate count (dSPC) method to overcome this hurdle. Instead of cultivating on agar plates, bacteria are encapsulated in monodisperse microdroplets for single-cell cultivation...
May 18, 2018: Analyst
https://www.readbyqxmd.com/read/29774830/frequent-implication-of-multistress-tolerant-campylobacter-jejuni-in-human-infections
#14
Euna Oh, Linda Chui, Junghee Bae, Vincent Li, Angela Ma, Steven K Mutschall, Eduardo N Taboada, Lynn M McMullen, Byeonghwa Jeon
Campylobacter jejuni, a major cause of bacterial foodborne illnesses, is considered highly susceptible to environmental stresses. In this study, we extensively investigated the stress tolerance of 121 clinical strains of C. jejuni against 5 stress conditions (aerobic stress, disinfectant exposure, freeze-thaw, heat treatment, and osmotic stress) that this pathogenic bacterium might encounter during foodborne transmission to humans. In contrast to our current perception about high stress sensitivity of C. jejuni, a number of clinical strains of C...
June 2018: Emerging Infectious Diseases
https://www.readbyqxmd.com/read/29774751/evaluation-of-articular-cartilage-injury-using-computed-tomography-with-axial-traction-in-the-ankle-joint
#15
Tomoyuki Nakasa, Yasunari Ikuta, Mikiya Sawa, Masahiro Yoshikawa, Yusuke Tsuyuguchi, Yuki Ota, Munekazu Kanemitsu, Nobuo Adachi
BACKGROUND: Although chondral or osteochondral injuries are usually assessed by magnetic resonance imaging, its accuracy can be low, presumably related to the relatively thin cartilage layer and the close apposition of the cartilage of the talus and tibial plafond. We hypothesized that axial traction could provide a contrast between the articular cartilage and joint cavity, and it enabled the simultaneous evaluation of cartilage and subchondral bone. The purpose of this study was to assess the feasibility of using computed tomography (CT) imaging with axial traction for the diagnosis of articular cartilage injuries...
May 1, 2018: Foot & Ankle International
https://www.readbyqxmd.com/read/29774576/spatial-vision-in-older-adults-perceptual-changes-and-neural-bases
#16
REVIEW
Allison M McKendrick, Yu Man Chan, Bao N Nguyen
PURPOSE: The number of older adults is rapidly increasing internationally, leading to a significant increase in research on how healthy ageing impacts vision. Most clinical assessments of spatial vision involve simple detection (letter acuity, grating contrast sensitivity, perimetry). However, most natural visual environments are more spatially complicated, requiring contrast discrimination, and the delineation of object boundaries and contours, which are typically present on non-uniform backgrounds...
May 17, 2018: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/29774398/improved-detection-of-a-tumorous-involvement-of-the-mesorectal-fascia-and-locoregional-lymph-nodes-in-locally-advanced-rectal-cancer-using-dce-mri
#17
Marco Armbruster, Melvin D'Anastasi, Veronika Holzner, Martin E Kreis, Olaf Dietrich, Bernhard Brandlhuber, Anno Graser, Martina Brandlhuber
PURPOSE: The prediction of an infiltration of the mesorectal fascia (MRF) and malignant lymph nodes is essential for treatment planning and prognosis of patients with rectal cancer. The aim of this study was to assess the additional diagnostic value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for the detection of a malignant involvement of the MRF and of mesorectal lymph nodes in patients with locally advanced rectal cancer. METHODS: In this prospective study, 22 patients with locally advanced rectal cancer were examined with 1...
May 17, 2018: International Journal of Colorectal Disease
https://www.readbyqxmd.com/read/29774185/protein-modified-ultra-small-gold-clusters-for-dual-modal-in-vivo-fluorescence-photoacoustic-imaging
#18
Duyang Gao, Yubin Liu, Yating Wang, Zhen Yuan
Background: Construction of nanoprobes for dual-modal fluorescence/photoacoustic imaging (PAI) is of great importance for the detection of disease pathology and the development of innovative therapeutics. Previously ultra-small gold clusters were designed and used as contrast agents for fluorescence imaging (FLI). However, it is not clear whether they can also serve as promising probes for PAI. In this study, protein-modified ultra-small gold clusters are produced and examined quantitatively as enhanced contrast agents for dual-modal in vivo fluorescence and PAI...
April 2018: Quantitative Imaging in Medicine and Surgery
https://www.readbyqxmd.com/read/29773755/expectations-do-not-alter-early-sensory-processing-during-perceptual-decision-making
#19
Nuttida Rungratsameetaweemana, Sirawaj Itthipuripat, Annalisa Salazar, John T Serences
Two factors play an important role in shaping perception: the allocation of selective attention to behaviorally relevant sensory features, and prior expectations about regularities in the environment. Signal detection theory proposes distinct roles of attention and expectation on decision-making such that attention modulates early sensory processing whereas expectation influences the selection and execution of motor responses. Challenging this classic framework, recent studies suggest that expectations about sensory regularities enhance the encoding and accumulation of sensory evidence during decision-making...
May 17, 2018: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/29773299/diffusion-mri-in-acute-nervous-system-injury
#20
Matthew D Budde, Nathan P Skinner
Diffusion weighted magnetic resonance imaging (DWI) and related techniques such as diffusion tensor imaging (DTI) are uniquely sensitive to the microstructure of the brain and spinal cord. In the acute aftermath of nervous system injury, for example, DWI reveals changes caused by injury that remains invisible on other MRI contrasts such as T2 -weighted imaging. This ability has led to a demonstrated clinical utility in cerebral ischemia. However, despite strong promise in preclinical models and research settings, DWI has not been as readily adopted for other acute injuries such as traumatic spinal cord, brain, or peripheral nerve injury...
April 30, 2018: Journal of Magnetic Resonance
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