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https://www.readbyqxmd.com/read/28531986/biomimicking-synthesis-of-photoluminescent-molecular-lantern-catalyzed-by-in-situ-formation-of-nanogold-catalysts
#1
Yong Yu, Xin Ting Zheng, Boon Wei Yee, Yen Nee Tan
Bioluminescence has been widely recognized as a powerful imaging tool for biological investigations. Synthesis of molecular lanterns that mimic bioluminescence in nature is of great interest. Herein we report a synthesis of molecular lantern by utilizing the catalytic properties of ultrasmall (<2nm) gold nanoclusters (AuNC), which is inspired by the enzymatic light-up of luciferin in the biological system. Small molecules such as hydroquinone and Cys-Gly peptides are used to direct the synthesis of AuNC via a biotemplating approach, while the in-situ formation of AuNC simultaneously catalyze the formation of luciferin-like, brightly fluorescent dye (λem=520nm, QY=0...
August 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28531876/photofunctionalization-of-dental-zirconia-oxide-surface-modification-to-improve-bio-integration-preserving-crystal-stability
#2
Marco Roy, Alfonso Pompella, Jerzy Kubacki, Adam Piosik, Bronisław Psiuk, Joanna Klimontko, Jacek Szade, Robert A Roy, Wieslaw Hedzelek
The use of zirconium oxide in dental implantology is rapidly increasing as it is regarded as being more aesthetical and biologically friendly than titanium oxide. The interaction of titanium oxide with cells and proteins has proven to be significantly affected by the inevitable atmospheric hydrocarbon contamination, defined as biological ageing. The latter has proven to be effectively reversed by UVC irradiation. Crystal structures of both Zr and Ti oxides are very similar, thus also ZrO2 is prone to contamination by hydrocarbons...
May 12, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28531862/unravelling-the-suitability-of-biological-induction-for-halophilic-lipase-production-by-halomonas-sp-lm1c-cultures
#3
Esther Gutiérrez-Arnillas, María Arellano, Francisco J Deive, Ana Rodríguez, María Ángeles Sanromán
In this study, the viability of using biological induction as an alternative to the conventional chemical induction in lipase production by a novel halophilic microorganism, Halomonas sp. LM1C, has been demonstrated. Thus, a 9-times increase of lipase activity (3000U/L) was recorded when Staphylococcus equorum sp. AMC7 was present in the medium, which is competitive with the results obtained when Triton X-100 was added as chemical inducer. The GC-MS data allowed concluding the true nature of the biological inducer effect, as the existence of high percentages of isomeric forms of pentadecanoic acid were detected...
May 4, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28531823/correlates-of-khat-use-during-pregnancy-a-cross-sectional-study
#4
Motohiro Nakajima, Mulusew G Jebena, Mohammed Taha, Markos Tesfaye, Esayas Gudina, Andrine Lemieux, Richard Hoffman, Mustafa al'Absi
OBJECTIVES: Khat is widely used in East African countries including Ethiopia. A growing body of evidence indicates that long-term khat use is associated with various health consequences. The aim of this study was to examine the magnitude and correlates of khat use in pregnant women. METHODS: This study used a cross-sectional, face-to-face interview design that included 642 pregnant women receiving antenatal care services at primary care centers in Ethiopia. A series of chi-square tests and regression models were conducted to examine whether khat use status (i...
May 9, 2017: Addictive Behaviors
https://www.readbyqxmd.com/read/28531805/troxerutin-txn-potentiated-5-fluorouracil-5-fu-treatment-of-human-gastric-cancer-through-suppressing-stat3-nf-%C3%AE%C2%BAb-and-bcl-2-signaling-pathways
#5
Gui-Yun Xu, Xiao-Jun Tang
Gastric cancer still presents a significant problem for public health worldwide. Troxerutin (TXN), a flavonoid present in tea, coffee, cereal grains, and a variety of fruits and vegetables, exhibits various pharmacological and biological activities in vitro and in vivo. We investigated the ability of TXN to reverse the in vitro and in vivo drug resistance of human gastric cancer cells, which were resistant to treatment of 5-Fluorouracil (5-FU). 5-Fu is a pyrimidine analog, which is widely used in the treatment of cancers...
May 19, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28531795/coherence-and-polarization-properties-of-laser-propagating-through-biological-tissues
#6
Duan Meiling, Zhang Chao, Li Jinhong
Based on the extended Huygens-Fresnel principle, the analytical expressions of the cross-spectral density matrix elements for random electromagnetic Gaussian Schell-model (GSM) beam propagating in biological tissues are derived, and used to study the changes in spectral degree of coherence μ and spectral degree of polarization P of random electromagnetic GSM beams with the propagation distance z propagating through the different biological tissues. It is shown that the changes closely depend on the species of the biological tissues, beam wave length, the interval between two field points and propagation distance...
May 9, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28531342/prognostic-significance-of-preoperative-neutrophilia-on-recurrence-free-survival-in-meningioma
#7
Shirin Karimi, Mana V Vyas, Lior Gonen, Raha Tabasinejad, Quinn Ostrom, Jill Barnholtz-Sloan, Suganth Suppiah, Gelareh Zadeh, Kenneth Aldape
Background: Meningioma is the most common primary intracranial tumor and recurrence is one of the important challenges in patient management. Prognostic factors for tumor recurrences in these patients especially before surgical resection are not fully characterized. Several studies have indicated an association between changes in hematologic laboratory parameters with patient outcomes in solid malignancies. We aimed to assess the association between hematological parameters and tumor recurrence in patients with meningioma...
May 20, 2017: Neuro-oncology
https://www.readbyqxmd.com/read/28531269/change-in-the-rate-of-biological-aging-in-response-to-caloric-restriction-calerie-biobank-analysis
#8
Daniel W Belsky, Kim M Huffman, Carl F Pieper, Idan Shalev, William E Kraus
Biological aging measures have been proposed as proxies for extension of healthy lifespan in trials of geroprotective therapies that aim to slow aging. Several methods to measure biological aging show promise; but it is not known if these methods are sensitive to changes caused by geroprotective therapy. We conducted analysis of two proposed methods to quantify biological aging using data from a recently concluded trial of an established geroprotector, caloric restriction. We obtained data from the National Institute on Aging CALERIE randomized trial through its public-access biobank (https://calerie...
May 22, 2017: Journals of Gerontology. Series A, Biological Sciences and Medical Sciences
https://www.readbyqxmd.com/read/28531219/pyldm-an-open-source-package-for-lifetime-density-analysis-of-time-resolved-spectroscopic-data
#9
Gabriel F Dorlhiac, Clyde Fare, Jasper J van Thor
Ultrafast spectroscopy offers temporal resolution for probing processes in the femto- and picosecond regimes. This has allowed for investigation of energy and charge transfer in numerous photoactive compounds and complexes. However, analysis of the resultant data can be complicated, particularly in more complex biological systems, such as photosystems. Historically, the dual approach of global analysis and target modelling has been used to elucidate kinetic descriptions of the system, and the identity of transient species respectively...
May 22, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28531195/livestock-metabolomics-and-the-livestock-metabolome-a-systematic-review
#10
Seyed Ali Goldansaz, An Chi Guo, Tanvir Sajed, Michael A Steele, Graham S Plastow, David S Wishart
Metabolomics uses advanced analytical chemistry techniques to comprehensively measure large numbers of small molecule metabolites in cells, tissues and biofluids. The ability to rapidly detect and quantify hundreds or even thousands of metabolites within a single sample is helping scientists paint a far more complete picture of system-wide metabolism and biology. Metabolomics is also allowing researchers to focus on measuring the end-products of complex, hard-to-decipher genetic, epigenetic and environmental interactions...
2017: PloS One
https://www.readbyqxmd.com/read/28531187/multi-scale-computational-study-of-the-mechanical-regulation-of-cell-mitotic-rounding-in-epithelia
#11
Ali Nematbakhsh, Wenzhao Sun, Pavel A Brodskiy, Aboutaleb Amiri, Cody Narciso, Zhiliang Xu, Jeremiah J Zartman, Mark Alber
Mitotic rounding during cell division is critical for preventing daughter cells from inheriting an abnormal number of chromosomes, a condition that occurs frequently in cancer cells. Cells must significantly expand their apical area and transition from a polygonal to circular apical shape to achieve robust mitotic rounding in epithelial tissues, which is where most cancers initiate. However, how cells mechanically regulate robust mitotic rounding within packed tissues is unknown. Here, we analyze mitotic rounding using a newly developed multi-scale subcellular element computational model that is calibrated using experimental data...
May 22, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28531184/bacarena-individual-based-metabolic-modeling-of-heterogeneous-microbes-in-complex-communities
#12
Eugen Bauer, Johannes Zimmermann, Federico Baldini, Ines Thiele, Christoph Kaleta
Recent advances focusing on the metabolic interactions within and between cellular populations have emphasized the importance of microbial communities for human health. Constraint-based modeling, with flux balance analysis in particular, has been established as a key approach for studying microbial metabolism, whereas individual-based modeling has been commonly used to study complex dynamics between interacting organisms. In this study, we combine both techniques into the R package BacArena (https://cran.r-project...
May 22, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28531167/a-role-for-the-host-dna-damage-response-in-hepatitis-b-virus-cccdna-formation-and-beyond
#13
REVIEW
Sabrina Schreiner, Michael Nassal
Chronic hepatitis B virus (HBV) infection puts more than 250 million people at a greatly increased risk to develop end-stage liver disease. Like all hepadnaviruses, HBV replicates via protein-primed reverse transcription of a pregenomic (pg) RNA, yielding an unusually structured, viral polymerase-linked relaxed-circular (RC) DNA as genome in infectious particles. Upon infection, RC-DNA is converted into nuclear covalently closed circular (ccc) DNA. Associating with cellular proteins into an episomal minichromosome, cccDNA acts as template for new viral RNAs, ensuring formation of progeny virions...
May 22, 2017: Viruses
https://www.readbyqxmd.com/read/28531107/analysis-of-gene-expression-signatures-in-cancer-associated-stroma-from-canine-mammary-tumours-reveals-molecular-homology-to-human-breast-carcinomas
#14
Julia Ettlin, Elena Clementi, Parisa Amini, Alexandra Malbon, Enni Markkanen
Cancer-associated stroma (CAS) plays a key role in cancer initiation and progression. Spontaneously occurring canine mammary carcinomas are viewed as excellent models of human breast carcinomas. Considering the importance of CAS for human cancer, it likely plays a central role in canine tumours as well. So far, however, canine CAS lacks characterisation, and it remains unclear whether the biology between CAS from canine and human tumours is comparable. In this proof-of-principle study, using laser-capture microdissection, we isolated CAS and normal stroma from 13 formalin-fixed paraffin embedded canine simple mammary carcinomas and analysed the expression of seven known human CAS markers by RT-qPCR (Reverse Transcription quantitative PCR) and validated some targets by immunohistochemistry...
May 20, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28530548/critical-role-of-rig-i-and-mda5-in-early-and-late-stages-of-tulane-virus-infection
#15
Preeti Chhabra, Priya Ranjan, Theresa Cromeans, Suryaprakash Sambhara, Jan Vinjé
Human noroviruses are a major cause of acute gastroenteritis worldwide, but the lack of a robust cell culture system or small animal model have hampered a better understanding of innate immunity against these viruses. Tulane virus (TV) is the prototype virus of a tentative new genus, Recovirus, in the family Caliciviridae. Its epidemiology and biological properties most closely resemble human norovirus. The host innate immune response to RNA virus infection primarily involves pathogen-sensing toll-like receptors (TLRs) TLR3 and TLR7 and retinoic acid-inducible gene I-like receptor RIG-I and melanoma differentiation associated gene 5 (MDA5)...
May 22, 2017: Journal of General Virology
https://www.readbyqxmd.com/read/28530340/-can-post-traumatic-stress-disorder-be-prevented-with-glucocorticoids
#16
REVIEW
Hagit Cohen, Zeev Kaplan, Joseph Zohar
Glucocorticoids (GCs) play a major role in orchestrating the complex physiological and behavioral reactions essential for the maintenance of homeostasis. These compounds enable the organism to prepare for, respond to and cope with the acute demands of physical and emotional stressors. The appropriate GC release, commensurate with stressor severity, enables the body to properly contain stress responses so as to promote recovery by rapidly restoring homeostasis. Indeed, inadequate GC release following stress not only delays recovery by disrupting biological homeostasis in the short run but can also interfere with the processing or interpretation of stressful information that results in long-term disruptions in memory integration...
December 2016: Harefuah
https://www.readbyqxmd.com/read/28530245/shifting-the-optimal-stiffness-for-cell-migration
#17
Benjamin L Bangasser, Ghaidan A Shamsan, Clarence E Chan, Kwaku N Opoku, Erkan Tüzel, Benjamin W Schlichtmann, Jesse A Kasim, Benjamin J Fuller, Brannon R McCullough, Steven S Rosenfeld, David J Odde
Cell migration, which is central to many biological processes including wound healing and cancer progression, is sensitive to environmental stiffness, and many cell types exhibit a stiffness optimum, at which migration is maximal. Here we present a cell migration simulator that predicts a stiffness optimum that can be shifted by altering the number of active molecular motors and clutches. This prediction is verified experimentally by comparing cell traction and F-actin retrograde flow for two cell types with differing amounts of active motors and clutches: embryonic chick forebrain neurons (ECFNs; optimum ∼1 kPa) and U251 glioma cells (optimum ∼100 kPa)...
May 22, 2017: Nature Communications
https://www.readbyqxmd.com/read/28530198/improved-bioavailability-and-pharmacokinetics-of-tea-polyphenols-by-encapsulation-into-gelatin-nanoparticles
#18
Karikalan Kulandaivelu, Abul Kalam Azad Mandal
The authors prepared surface modified (with polyelectrolyte layers), tea polyphenols (TPP) encapsulated, gelatin nanoparticles (TPP-GNP) and characterised them. The size of the spherical nanoparticles was ∼50 nm. Number of polyelectrolyte layers and incubation time influenced the encapsulation efficiency (EE); highest EE was noted in nanoparticles with six polyelectrolyte layers (TPP-GNP-6L) incubated for 4 h. TPP released from TPP-GNP-6L in simulated biological fluids indicated protection and controlled release of TPP due to encapsulation...
June 2017: IET Nanobiotechnology
https://www.readbyqxmd.com/read/28529754/chitosan-poly-caprolactone-nanofibers-for-skin-repair
#19
Sheeny Lan Levengood, Ariane E Erickson, Fei-Chien Chang, Miqin Zhang
Dermal wounds, both acute and chronic, represent a significant clinical challenge and therefore the development of novel biomaterial-based skin substitutes to promote skin repair is essential. Nanofibers have garnered attention as materials to promote skin regeneration due to the similarities in morphology and dimensionality between nanofibers and native extracellular matrix proteins, which are critical in guiding cutaneous wound healing. Electrospun chitosan-poly(caprolactone) (CPCL) nanofiber scaffolds, which combine the important intrinsic biological properties of chitosan and the mechanical integrity and stability of PCL, were evaluated as skin tissue engineering scaffolds using a mouse cutaneous excisional skin defect model...
March 7, 2017: Journal of Materials Chemistry. B, Materials for Biology and Medicine
https://www.readbyqxmd.com/read/28529635/synthesis-of-5-18-f-fluoro-%C3%AE-methyl-tryptophan-new-trp-based-pet-agents
#20
Benjamin C Giglio, Haiyang Fei, Mengzhe Wang, Hui Wang, Liu He, Huijuan Feng, Zhanhong Wu, Hongjian Lu, Zibo Li
Indoleamine 2,3-dioxygenase (IDO1) plays a special role in the biology of various cancer types, because it breaks down the essential amino acid tryptophan for immune cell activation. Upregulation of IDO1 significantly correlates with the number of various T cell types in tumor tissues in melanoma and other cancers, suggesting that IDO expression is linked with effective and ineffective ('exhausted') immune response in cancer. Based on the reported IDO inhibitors (α-Methylated and indole-N-methylated tryptophan (Trp)), here we report the synthesis of potential IDO1 imaging agents through direct introduction of (18)F into the tryptophan aromatic ring...
2017: Theranostics
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