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https://www.readbyqxmd.com/read/28818654/water-based-fractionation-of-a-commercial-humic-acid-solid-state-and-colloidal-characterization-of-the-solubility-fractions
#1
Weronika M Swiech, Ian Hamerton, Huang Zeng, David J Watson, Eleonore Mason, Spencer E Taylor
BACKGROUND AND HYPOTHESIS: Humic acid (HA) is of considerable environmental significance, being a major component of soil, as well as being considered for application in other technological areas. However, its structure and colloidal properties continue to be the subject of debate, largely owing to its molecular complexity and association with other humic substances and mineral matter. As a class, HA is considered to comprise supramolecular assemblies of heterogeneous species, and herein we consider a simple route for the separation of some HA sub-fractions...
August 12, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/28815595/sigma-1-receptor-ligands-inhibit-catecholamine-secretion-from-adrenal-chromaffin-cells-due-to-block-of-nicotinic-acetylcholine-receptors
#2
Rebecca L Brindley, Mary Beth Bauer, Nolan D Hartley, Kyle J Horning, Kevin P M Currie
Adrenal chromaffin cells (ACCs) are the neuroendocrine arm of the sympathetic nervous system and key mediators of the physiological stress response. Acetylcholine (ACh) released from preganglionic splanchnic nerves activates nicotinic acetylcholine receptors (nAChRs) on chromaffin cells causing membrane depolarization, opening voltage-gated Ca(2+) channels (VGCC), and exocytosis of catecholamines and neuropeptides. The serotonin transporter (SERT) is expressed in ACCs and interacts with 5-HT1A receptors to control secretion...
August 16, 2017: Journal of Neurochemistry
https://www.readbyqxmd.com/read/28813617/environmental-stress-affects-the-formation-of-staphylococcus-aureus-persisters-tolerant-to-antibiotics
#3
Lucie Kubistova, Lukas Dvoracek, Jan Tkadlec, Oto Melter, Irena Licha
The ability to form persisters has been observed in many microorganisms, including Staphylococcus aureus, mainly in the context of chronic infections and the pathogenicity of these microbes. In our research, we have demonstrated that salt or oxidative stress could play a role in the formation of S. aureus persisters outside the host's intracellular interface. We pre-exposed planktonic growing bacterial culture to an oxidative or salt stress and monitored the dynamics of persister formation after ciprofloxacin and gentamicin treatment...
August 16, 2017: Microbial Drug Resistance: MDR: Mechanisms, Epidemiology, and Disease
https://www.readbyqxmd.com/read/28812884/controlling-bdellovibrio-bacteriovorus-gene-expression-and-predation-using-synthetic-riboswitches
#4
Mohammed Dwidar, Yohei Yokobayashi
Bdellovibrio bacteriovorus is a predatory bacterium that feeds on Gram-negative bacteria including a wide range of pathogens and thus has potential applications as a biocontrol agent. Owing to its unique life cycle, however, there are limited tools that enable genetic manipulation of B. bacteriovorus. This work describes our first steps toward engineering the predatory bacterium for practical applications by developing basic genetic parts to control gene expression. Specifically, we evaluated four robust promoters that are active during the attack phase of B...
August 18, 2017: ACS Synthetic Biology
https://www.readbyqxmd.com/read/28812206/differences-in-femoral-neck-structure-between-elderly-caucasian-and-chinese-populations-a-cross-sectional-study-of-perth-beijing-cohorts
#5
L Wang, B C C Khoo, X G Cheng, K Brown, J R Lewis, Y B Su, Z Guo, K Li, R L Prince
Structural skeletal differences of the femoral neck of older Beijing-Chinese and Perth-Caucasian women were compared; adjusting for frame size-related differences, Beijing-Chinese have lower periosteal width; however, indices of internal bone distribution suggest that Beijing-Chinese may exhibit increased resistance to fracture that may relate to the reduced hip fracture incidence. INTRODUCTION: Ethnic differences in skeletal structure may relate to differences in hip fracture risk in Chinese and Caucasian populations...
August 15, 2017: Archives of Osteoporosis
https://www.readbyqxmd.com/read/28811536/ige-trimers-drive-spe-7-cytokinergic-activity
#6
Heather J Bax, Holly Bowen, Rebecca L Beavil, Raymond Chung, Malcolm Ward, Anna M Davies, Tihomir S Dodev, James M McDonnell, Andrew J Beavil, Brian J Sutton, Hannah J Gould
Degranulation of mast cells and basophils, with release of agents of the allergic response, ensues when multivalent antigens bind to and cross-link the cells' receptor-bound IgE antibodies. A widely used commercial monoclonal IgE antibody, SPE-7 IgE from Sigma, was found to possess the radically anomalous property, termed "cytokinergic", of inducing basophil degranulation without the intervention of an antigen. We show here that the IgE monomer, freed of protein contaminants, is devoid of this activity, and that the source of the anomaly is a trace impurity, identified as a dissociation-resistant IgE trimer...
August 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28809452/neurotoxin-synthesis-is-positively-regulated-by-the-sporulation-transcription-factor-spo0a-in-clostridium-botulinum-type-e
#7
Gerald Mascher, Anna Mertaoja, Hannu Korkeala, Miia Lindström
Clostridium botulinum produces the most potent natural toxin, the botulinum neurotoxin (BoNT), probably to create anaerobiosis and nutrients by killing the host, and forms endospores that facilitate survival in harsh conditions and transmission. Peak BoNT production coincides with initiation of sporulation in C. botulinum cultures, which suggests common regulation. Here we show that Spo0A, the master regulator of sporulation, positively regulates BoNT production. Insertional inactivation of spo0A in C. botulinum type E strain Beluga resulted in significantly reduced BoNT production and in abolished or highly reduced sporulation in relation to wild-type controls...
August 15, 2017: Environmental Microbiology
https://www.readbyqxmd.com/read/28805650/the-status-of-varying-constants-a-review-of-the-physics-searches-and-implications
#8
Carlos J A P Martins
The observational evidence for the recent acceleration of the universe demonstrates that canonical theories of cosmology and particle physics are incomplete-if not incorrect-and that new physics is out there, waiting to be discovered. A key task for the next generation of laboratory and astrophysical facilities is to search for, identify and ultimately characterize this new physics. Here we highlight recent developments in tests of the stability of nature's fundamental couplings, which provide a direct handle on new physics: a detection of variations will be revolutionary, but even improved null results provide competitive constraints on a range of cosmological and particle physics paradigms...
August 14, 2017: Reports on Progress in Physics
https://www.readbyqxmd.com/read/28803983/molecular-structure-of-a-prostaglandin-d-synthase-requiring-glutathione-from-the-brown-planthopper-nilaparvata-lugens
#9
Kohji Yamamoto, Akifumi Higashiura, Mamoru Suzuki, Kosuke Aritake, Yoshihiro Urade, Atsushi Nakagawa
Prostaglandins are involved in many physiological processes, and prostaglandin synthases facilitate the detoxification of xenobiotics as well as endogenous compounds, such as through glutathione conjugation. Specifically, prostaglandin D synthase (PGDS) catalyzes the isomerization of PGH2 to PGD2. Here we report the identification and structural analysis of PGDS from the brown planthopper rice pest Nilaparvata lugens (nlPGDS), which belongs to the sigma-class glutathione transferases. The structure of nlPGDS in complex with glutathione was determined at a resolution of 2...
August 10, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28802412/mycobacterium-tuberculosis-sige-mutant-st28-used-as-a-vaccine-induces-protective-immunity-in-the-guinea-pig-model
#10
JoLynn Troudt, Elizabeth Creissen, Linda Izzo, Helle Bielefeldt-Ohmann, Stefano Casonato, Riccardo Manganelli, Angelo A Izzo
With more than 9 million new infections and 1.5 million deaths claimed every year, tuberculosis remains one of the major scourges of humankind. The only vaccine available against this disease, the attenuated strain Mycobacterium bovis, BCG is effective against severe forms of the disease in infants, but scarcely effective in protecting adults from the pulmonary form of the disease, thus not stopping transmission. Consequently, the development of an effective anti-tuberculosis vaccine is a major goal for improving global health...
September 2017: Tuberculosis
https://www.readbyqxmd.com/read/28802275/response-of-methylocystis-sp-strain-sc2-to-salt-stress-physiology-global-transcriptome-and-amino-acid-profiles
#11
Dongfei Han, Hannes Link, Werner Liesack
Soil microorganisms have to rapidly respond to salt-induced osmotic stress. Type II methanotrophs of the genus Methylocystis are widely distributed in upland soils, but are known to have a low salt tolerance. Here, we tested the ability of Methylocystis sp. strain SC2 to adapt to increased salinity. When exposed to 0.75% NaCl, methane oxidation was completely inhibited for 2.25 h and fully recovered within 6 h. Growth was inhibited for 23.5 h and then fully recovered. Its transcriptome was profiled after 0 min (control), 45 min (early response) and 14 h (late response) of stress exposure...
August 11, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28798726/systems-biology-analysis-of-temporal-in-vivo-brucella-melitensis-and-bovine-transcriptomes-predicts-host-pathogen-protein-protein-interactions
#12
Carlos A Rossetti, Kenneth L Drake, Sara D Lawhon, Jairo S Nunes, Tamara Gull, Sangeeta Khare, Leslie G Adams
To date, fewer than 200 gene-products have been identified as Brucella virulence factors, and most were characterized individually without considering how they are temporally and coordinately expressed or secreted during the infection process. Here, we describe and analyze the in vivo temporal transcriptional profile of Brucella melitensis during the initial 4 h interaction with cattle. Pathway analysis revealed an activation of the "Two component system" providing evidence that the in vivo Brucella sense and actively regulate their metabolism through the transition to an intracellular lifestyle...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28792792/the-effect-of-rgd-ngr-peptide-modification-of-melanoma-differentiation-associated-gene-7-interleukin-24-on-its-receptor-attachment-an-in-silico-analysis
#13
Samaneh Bina, Seyed Younes Hosseini, Fatemeh Shenavar, Ebrahim Hosseini, Mojtaba Mortazavi
Melanoma differentiation-associated gene-7 (mda-7/interleukin [IL]-24), a unique tumor suppressor gene, induces selective apoptosis in tumor cells. Secreted IL-24 binds to heterodimeric receptor complexes of IL-20R1/IL-20R2, IL-22R1/IL-20R2, or sigma-1 receptor (Sig1R) that consequently enhances apoptosis. However, this mechanism is not well understood and most likely involves different pathways. Targeting of cytokine by tumor homing peptides (THPs) to the tumor cell surface molecule-like integrin shows to be beneficial in gene immunotherapy approaches...
August 2017: Cancer Biotherapy & Radiopharmaceuticals
https://www.readbyqxmd.com/read/28791824/anti-enterococcal-activities-of-pentacyclic-triterpenes
#14
Dorota Wojnicz, Dorota Tichaczek-Goska, Kamila Korzekwa, Marta Kicia, Andrzej Hendrich
BACKGROUND: Asiatic (AA) and ursolic (UA) acids are widely studied phytochemicals, but their antimicrobial properties are still poorly understood. Therefore our research has focused on their activity against uropathogenic Enterococcus faecalis strains. OBJECTIVES: The aim of this research was to determine the influence of AA and UA on the growth, cell morphology, virulence factors and biofilm formation by E. faecalis strains. MATERIAL AND METHODS: AA and UA were purchased from Sigma-Aldrich...
May 2017: Advances in Clinical and Experimental Medicine: Official Organ Wroclaw Medical University
https://www.readbyqxmd.com/read/28791385/sigma-1-receptor-activation-ameliorates-anxiety-like-behavior-through-nr2a-creb-bdnf-signaling-pathway-in-a-rat-model-submitted-to-single-prolonged-stress
#15
Li-Li Ji, Jun-Bo Peng, Chang-Hai Fu, Lei Tong, Zhen-Yu Wang
Accumulating evidence has demonstrated that the σ-1 receptor (σ‑1R) possesses neuroprotective effects and is a potential novel therapeutic target for certain psychiatric diseases, including post‑traumatic stress disorder (PTSD) accompanied with anxiety disorder. It has been reported that σ‑1R agonist treatment could be modulated by the brain‑derived neurotrophic factor (BDNF) signaling pathway. However, it remains unclear whether BDNF and its upstream regulator are mechanistically involved in the therapeutic effect of σ‑1R in PTSD...
August 7, 2017: Molecular Medicine Reports
https://www.readbyqxmd.com/read/28775215/observation-of-coherent-elastic-neutrino-nucleus-scattering
#16
D Akimov, J B Albert, P An, C Awe, P S Barbeau, B Becker, V Belov, A Brown, A Bolozdynya, B Cabrera-Palmer, M Cervantes, J I Collar, R J Cooper, R L Cooper, C Cuesta, D J Dean, J A Detwiler, A Eberhardt, Y Efremenko, S R Elliott, E M Erkela, L Fabris, M Febbraro, N E Fields, W Fox, Z Fu, A Galindo-Uribarri, M P Green, M Hai, M R Heath, S Hedges, D Hornback, T W Hossbach, E B Iverson, L J Kaufman, S Ki, S R Klein, A Khromov, A Konovalov, M Kremer, A Kumpan, C Leadbetter, L Li, W Lu, K Mann, D M Markoff, K Miller, H Moreno, P E Mueller, J Newby, J L Orrell, C T Overman, D S Parno, S Penttila, G Perumpilly, H Ray, J Raybern, D Reyna, G C Rich, D Rimal, D Rudik, K Scholberg, B J Scholz, G Sinev, W M Snow, V Sosnovtsev, A Shakirov, S Suchyta, B Suh, R Tayloe, R T Thornton, I Tolstukhin, J Vanderwerp, R L Varner, C J Virtue, Z Wan, J Yoo, C-H Yu, A Zawada, J Zettlemoyer, A M Zderic
The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross-section is the largest by far of all low-energy neutrino couplings. This mode of interaction provides new opportunities to study neutrino properties, and leads to a miniaturization of detector size, with potential technological applications. We observe this process at a 6.7-sigma confidence level, using a low-background, 14.6-kg CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory...
August 3, 2017: Science
https://www.readbyqxmd.com/read/28774362/-intrauterine-growth-curves-for-body-weight-body-length-head-circumference-chest-circumference-and-crown-rump-length-in-16%C3%A2-887-neonates-with-a-gestational-age-of-27-42-weeks-in-shenzhen-china
#17
Xiao-Yun Huang, Hui-Long Liu, Min Lei, Hui-Fen Mai, Chao-Hui Lian, You-Cong Li
OBJECTIVE: To establish the intrauterine growth curves of neonates in Shenzhen, China and to investigate the intrauterine growth of neonates in Shenzhen. METHODS: Cross-sectional cluster sampling was performed for an on-the-spot investigation of 16 887 neonates (9 418 males and 7 469 females) with a gestational age of 27-42 weeks who were born in two hospitals in Shenzhen from April 2013 to September 2015. The Lambda Mu Sigma (LMS) method was used for the curve fitting of body weight, body length, head circumference, chest circumference, and crown-rump length...
August 2017: Zhongguo Dang Dai Er Ke za Zhi, Chinese Journal of Contemporary Pediatrics
https://www.readbyqxmd.com/read/28767411/sigma-1-and-sigma-2-receptor-ligands-induce-apoptosis-and-autophagy-but-have-opposite-effect-on-cell-proliferation-in-uveal-melanoma
#18
Lucia Longhitano, Carlo Castruccio Castracani, Daniele Tibullo, Roberto Avola, Maria Viola, Giuliano Russo, Orazio Prezzavento, Agostino Marrazzo, Emanuele Amata, Michele Reibaldi, Antonio Longo, Andrea Russo, Nunziatina Laura Parrinello, Giovanni Li Volti
Uveal melanoma is the most common primary intraocular tumor in adults, with about 1200-1500 new cases occurring per year in the United States. Metastasis is a frequent occurrence in uveal melanoma, and outcomes are poor once distant spread occurs and no clinically significant chemotherapeutic protocol is so far available. The aim of the present study was to test the effect of various σ1 and σ2 receptor ligands as a possible pharmacological strategy for this rare tumor. Human uveal melanoma cells (92.1) were treated with various concentrations of different σ2 ligands (haloperidol and haloperidol metabolite II) and σ1 ligand ((+)-pentazocine) at various concentrations (1, 10 and 25 μM) and time points (0, 4 h, 8 h, 24 h and 48 h)...
July 25, 2017: Oncotarget
https://www.readbyqxmd.com/read/28762183/novel-nanoformulation-to-mitigate-co-effects-of-drugs-of-abuse-and-hiv-1-infection-towards-the-treatment-of-neuroaids
#19
Rahul Dev Jayant, Venkata S R Atluri, Sneham Tiwari, Sudheesh Pilakka-Kanthikeel, Ajeet Kaushik, Adriana Yndart, Madhavan Nair
Drug abuse (e.g., methamphetamine-Meth or cocaine-Coc) is one of the major risk factors for becoming infected with HIV-1, and studies show that in combination, drug abuse and HIV-1 lead to significantly greater damage to CNS. To overcome these issues, we have developed a novel nanoformulation (NF) for drug-abusing population infected with HIV-1. In this work, a novel approach was developed for the co-encapsulation of Nelfinavir (Nel) and Rimcazole (Rico) using layer-by-layer (LbL) assembled magnetic nanoformulation for the cure of neuroAIDS...
July 31, 2017: Journal of Neurovirology
https://www.readbyqxmd.com/read/28761057/development-of-series-of-affinity-tags-in-streptomyces
#20
Xu-Ming Mao, Ning Sun, Yang Zheng, Yong-Quan Li
Streptomyces are of great biological and industrial significance due to their complex morphological development and ability to produce numerous secondary metabolites. However, the intrinsic biochemical mechanisms underlying morphogenesis and secondary metabolism are rarely revealed, partially because of the limited availability of the biochemical tools in Streptomyces. Here we provided series of integrative vectors with various affinity tags, including single tags 3×FLAG, 3×HA, 3×Strep-tag II, 18×His, 13×Myc, and dual tags, all of which were driven from a strong constitutive promoter ermEp*...
July 31, 2017: Scientific Reports
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