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https://www.readbyqxmd.com/read/29351247/b-type-and-complex-a-b-type-epicatechin-trimers-isolated-from-litchi-pericarp-aqueous-extract-show-high-antioxidant-and-anticancer-activity
#1
Yihui Gong, Fang Fang, Xin Zhang, Bin Liu, Honghui Luo, Zhen Li, Xuelian Zhang, Zhaoqi Zhang, Xuequn Pang
Litchi (Litchi chinensis Sonn.) fruit is known for its rich source of phenolics. Litchi pericarp contains high levels of epicatechin that may form oligomers of various lengths. Except for several A or B type epicatechin dimers, other soluble oligomers have rarely been identified in the pericarp. Here, bioassay-guided column fractionation was applied to isolate bioactive phenolics from aqueous pericarp extract. A fraction (S3) was obtained by two rounds of Sephadex LH-20 column chromatography, and showed higher antioxidant activity and inhibition on the proliferation of human lung cancer cells (A549) than Litchi anthocyanins...
January 19, 2018: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/29349741/degradation-behavior-of-triclosan-by-co-exposure-to-chlorine-dioxide-and-uv-irradiation-influencing-factors-and-toxicity-changes
#2
Qing-Song Li, Hui-Wen Cai, Guo-Xin Li, Guo-Yuan Chen, Xiao-Yan Ma, Wen-Long He
This study investigated the transformation of triclosan (TCS) following co-exposure to UV irradiation and ClO2. Special attention was given to understand the influencing of water quality parameters and toxicity changes during the co-exposure process. The results show that the co-exposure process prompted TCS elimination quickly and effectively, with more than 99% of TCS degraded under the experimental conditions. The molar yield ratios of 2,4-dichlorophenol/TCS (2,4-DCP/TCS) were calculated to be 35.81-74.49%; however, the by-product of 2,8-dichlorodibenzop-dioxin (2,8-Cl2DD) was not detected...
January 18, 2018: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29348586/analogues-of-disulfides-from-allium-stipitatum-demonstrate-potent-anti-tubercular-activities-through-drug-efflux-pump-and-biofilm-inhibition
#3
Cynthia A Danquah, Eleftheria Kakagianni, Proma Khondkar, Arundhati Maitra, Mukhlesur Rahman, Dimitrios Evangelopoulos, Timothy D McHugh, Paul Stapleton, John Malkinson, Sanjib Bhakta, Simon Gibbons
Disulfides from Allium stipitatum, commonly known as Persian shallot, were previously reported to possess antibacterial properties. Analogues of these compounds, produced by S-methylthiolation of appropriate thiols using S-methyl methanethiosulfonate, exhibited antimicrobial activity, with one compound inhibiting the growth of Mycobacterium tuberculosis at 17 µM (4 mg L-1) and other compounds inhibiting Escherichia coli and multi-drug-resistant (MDR) Staphylococcus aureus at concentrations ranging between 32-138 µM (8-32 mg L-1)...
January 18, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29347971/detection-and-dissemination-of-toxoplasma-gondii-in-experimentally-infected-calves-a-single-test-does-not-tell-the-whole-story
#4
Alison Burrells, Alessandra Taroda, Marieke Opsteegh, Gereon Schares, Julio Benavides, Cecile Dam-Deisz, Paul M Bartley, Francesca Chianini, Isabella Villena, Joke van der Giessen, Elisabeth A Innes, Frank Katzer
BACKGROUND: Although the detection of Toxoplasma gondii in bovine tissues is rare, beef might be an important source of human infection. The use of molecular techniques, such as magnetic capture qPCR (MC-qPCR), in combination with the gold standard method for isolating the parasite (mouse bioassay), may increase the sensitivity of T. gondii detection in infected cattle. The risk of transmission of the parasite to humans from undercooked/raw beef is not fully known and further knowledge about the predilection sites of T...
January 18, 2018: Parasites & Vectors
https://www.readbyqxmd.com/read/29346647/resistance-to-selected-pyrethroid-insecticides-in-the-malaria-mosquito-anopheles-stephensi-diptera-muscidae-from-punjab-pakistan
#5
Hafiz Azhar Ali Khan, Waseem Akram, Sumi Lee
Pyrethroids are commonly used insecticides in malaria control programs; however, insecticide resistance limits the benefits gained by using these insecticides. In the present study, we assessed the resistance status for different pyrethroids of the malaria mosquito vector, Anopheles stephensi Liston (Diptera: Muscidae), in the Punjab province, Pakistan. Bioassays were conducted using diagnostic doses following standard World Health Organization protocols: 0.05% λ-cyhalothrin, 0.75% permethrin, 0.15% cyfluthrin, 0...
January 16, 2018: Journal of Medical Entomology
https://www.readbyqxmd.com/read/29344803/toxoplasma-gondii-prevalence-and-characterization-of-new-genotypes-in-free-range-chickens-from-south-brazil
#6
Fernando Emmanuel Gonçalves Vieira, João Pedro Sasse, Ana Flávia Minutti, Ana Carolina Miura, Luiz Daniel de Barros, Sergio Tosi Cardim, Thais Agostinho Martins, Mércia de Seixas, Milton Issashi Yamamura, Chunlei Su, João Luis Garcia
Toxoplasma gondii is an intracellular parasite that can infect all warm-blooded animals including humans. Recent studies showed that T. gondii strains from South America are genetically diverse. The present work aimed to determine T. gondii prevalence in free-ranging chicken in northwest Parana state in Brazil by two serological tests, to isolate the parasites from seropositive chickens and to genotype the isolates. Antibodies to T. gondii in 386 serum samples from 24 farms were investigated by immunofluorescence antibody assay (IFA) and modified agglutination test (MAT)...
January 18, 2018: Parasitology Research
https://www.readbyqxmd.com/read/29342973/biogenic-weathering-solubilization-of-iron-from-minerals-by-epilithic-freshwater-algae-and-cyanobacteria
#7
George E Mustoe
A sandstone outcrop exposed to freshwater seepage supports a diverse assemblage of photosynthetic microbes. Dominant taxa are two cyanophytes (Oscillatoria sp., Rivularia sp.) and a unicellular green alga (Palmellococcus sp.). Less abundant taxa include a filamentous green alga, Microspora, and the desmid Cosmarium. Biologic activity is evidenced by measured levels of chlorophyll and lipids. Bioassay methods confirm the ability of these microbes to dissolve and metabolize Fe from ferruginous minerals. Chromatographic analysis reveals citric acid as the likely chelating agent; this low molecular weight organic acid is detectable in interstitial fluid in the sandstone, measured as 0...
January 15, 2018: Microorganisms
https://www.readbyqxmd.com/read/29341908/induction-of-au-methotrexate-conjugates-by-sugar-molecules-production-assembly-mechanism-and-bioassay-studies
#8
Wei-Yuan Wang, Xiu-Fen Zhao, Xiao-Han Ju, Ping Liu, Jing Li, Ya-Wen Tang, Shu-Ping Li, Xiao-Dong Li, Fu-Gui Song
Au-methotrexate (Au-MTX) conjugates induced by sugar molecules were produced by a simple, one-pot, hydrothermal growth method. Herein, the Au(III)-MTX complexes were used as the precursors to form Au-MTX conjugates. Addition of different types of sugar molecules with abundant hydroxyl groups resulted in the formation of Au-MTX conjugates featuring distinct characteristics that could be explained by the diverse capping mechanisms of sugar molecules. That is, the instant-capping mechanism of glucose favored the generation of peanut-like Au-MTX conjugates with high colloidal stability while the post-capping mechanism of dextran and sucrose resulted in the production of Au-MTX conjugates featuring excellent near-infrared (NIR) optical properties with a long-wavelength plasmon resonance near 630-760 nm...
January 13, 2018: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/29339452/effects-of-colostrum-feeding-method-and-oral-igf1-on-porcine-uterine-development
#9
Ashley F George, Kathleen M Rahman, Dori J Miller, Anne A Wiley, Meredith E Camp, Frank Bartol, Carol A Bagnell
Nursing ensures lactocrine delivery of maternally-derived, milk-borne bioactive factors to offspring, which affects postnatal development of female reproductive tract tissues. Disruption of lactocrine communication for two days from birth (postnatal day = PND 0) by feeding milk replacer in lieu of nursing or consumption of colostrum alters porcine uterine gene expression globally by PND 2 and inhibits uterine gland genesis by PND 14. Here, objectives were to determine effects of: 1) nursing or milk replacer feeding from birth; 2) a single dose of colostrum or milk replacer and method of feeding; and 3) a single feeding of colostrum or milk replacer, with or without oral supplementation of IGF1, administered at birth on aspects of porcine uterine development at 12 h postnatally...
January 16, 2018: Reproduction: the Official Journal of the Society for the Study of Fertility
https://www.readbyqxmd.com/read/29339245/systematic-review-and-evaluation-of-aspartame-carcinogenicity-bioassays-using-quality-criteria
#10
REVIEW
Lois Haighton, Ashley Roberts, Brandon Walters, Barry Lynch
The current review assessed cancer studies of aspartame based on a quality appraisal using the Klimisch grading system. Nine studies having complete histopathology were included: three 2-year studies by Searle; three transgenic mice studies by the NTP; three lifetime studies by the Ramazzini Institute. A tenth study limited to brain tumors was not rated. None were determined as Klimisch Code 1 (reliable without restrictions). The Searle studies predated GLP standards but their methodology was comparable; transgenic mouse models are not validated, but are accepted as supporting data...
January 12, 2018: Regulatory Toxicology and Pharmacology: RTP
https://www.readbyqxmd.com/read/29338238/paralithocins-antimicrobial-peptides-with-unusual-disulfide-connectivity-from-the-red-king-crab-paralithodes-camtschaticus
#11
Morten K Moe, Tor Haug, Magne O Sydnes, Sigmund V Sperstad, Chun Li, Lena C Vaagsfjord, Enrique de la Vega, Klara Stensvåg
As part of an ongoing exploration of marine invertebrates as a source of new antimicrobial peptides, hemocyte extracts from the red king crab, Paralithodes camtschaticus, were studied. Three cationic cysteine (Cys)-rich peptides, named paralithocins 1-3, were isolated by bioassay-guided purification, and their amino acid sequences determined by Edman degradation and expressed sequences tag analysis. Disulfide bond mapping was performed by high-resolution tandem mass spectrometry. The peptides (38-51 amino acids in length) share a unique Cys motif composed of eight Cys, forming four disulfide bridges with a bond connectivity of (Cys relative position) Cys1-Cys8, Cys2-Cys6, Cys3-Cys5, and Cys4-Cys7, a disulfide arrangement that has not been previously reported among antimicrobial peptides...
January 17, 2018: Journal of Natural Products
https://www.readbyqxmd.com/read/29337537/microplastic-effect-thresholds-for-freshwater-benthic-macroinvertebrates
#12
Paula E Redondo Hasselerharm, Dede Falahudin, Edwin Peeters, Albert A Koelmans
Now that microplastics have been detected in lakes, rivers and estuaries all over the globe, evaluating their effects on biota has become an urgent research priority. This is the first study that aims at determining the effect thresholds for a battery of six freshwater benthic macroinvertebrates with different species traits, using a wide range of microplastic concentrations. Standardized 28 d single species bioassays were performed under environmentally relevant exposure conditions using polystyrene microplastics (20 - 500 µm) mixed with sediment at concentrations ranging from 0 to 40% sediment dry weight (dw)...
January 16, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/29337192/combining-machine-learning-models-of-in-vitro-and-in-vivo-bioassays-improves-rat-carcinogenicity-prediction
#13
Davy Guan, Kevin Fan, Ian Spence, Slade Matthews
In vitro genotoxicity bioassays are cost-efficient methods of assessing potential carcinogens. However, many genotoxicity bioassays are inappropriate for detecting chemicals eliciting non-genotoxic mechanisms, such as tumour promotion, this necessitates the use of in vivo rodent carcinogenicity (IVRC) assays. In silico IVRC modelling could potentially address the low throughput and high cost of this assay. We aimed to develop and combine computational QSAR models of novel bioassays for the prediction of IVRC results and compare with existing software...
January 11, 2018: Regulatory Toxicology and Pharmacology: RTP
https://www.readbyqxmd.com/read/29336243/identification-of-in-vitro-red-fluorescent-protein-with-antipathogenic-activity-from-the-midgut-of-the-silkworm-bombyx-mori-l
#14
Manjunatha Ks Gowda, Anitha Peter, Mahantesha Bn Naika, P Niranjana, P Shamprasad
Biotic stress affects all organisms, including the silkworm (Bombyx mori L.) which also has a plethora of defense mechanisms against the infecting pathogens. The midgut plays an important role as a natural barrier and source of innate immunity. The present investigation was thus undertaken to identify an antiviral red fluorescent protein formed in the midgut of the silkworm Bombyx mori L. The digestive juice from fifth instar Kolar Gold silkworm larvae was collected and subjected to 40 % ammonium sulfate precipitation and purified by gel filtration chromatography (GFC)...
January 15, 2018: Protein and Peptide Letters
https://www.readbyqxmd.com/read/29336151/ultra-robust-biochips-with-metal-organic-framework-coating-for-point-of-care-diagnosis
#15
Congzhou Wang, Lu Wang, Sirimuvva Tadepalli, Jeremiah J Morrissey, Evan D Kharasch, Rajesh R Naik, Srikanth Singamaneni
Most biosensors relying on antibodies as recognition elements fail in harsh environment conditions such as elevated temperatures, organic solvents or proteases because of antibody denaturation, and require strict storage conditions with defined shelf-life, thus limiting their applications in point-of-care and resource-limited settings. Here, a metal-organic framework (MOF) encapsulation is utilized to preserve the biofunctionality of antibodies conjugated to nanotransducers. This study investigates several parameters of MOF coating (including growth time, surface morphology, thickness and precursor concentrations) that determine the preservation efficacy against different protein denaturing conditions in both dry and wet environments...
January 16, 2018: ACS Sensors
https://www.readbyqxmd.com/read/29335165/dioxins-furans-and-dioxin-like-pcbs-in-sediment-samples-and-suspended-particulate-matter-from-the-scheldt-estuary-and-the-north-sea-coast-comparison-of-calux-concentration-levels-in-historical-and-recent-samples
#16
T Vandermarken, Y Gao, W Baeyens, M S Denison, K Croes
BACKGROUND: The Scheldt estuary is historically a highly polluted river system. While several studies have focused on contamination with metals, pesticides, Polycyclic Aromatic Hydrocarbons (PAHs) and marker PolyChlorinated Biphenyls (PCBs), no data are available concerning past contamination by dioxin-like compounds. OBJECTIVES: The objective of this study is to determine spatial and time trends of PolyChlorinated Dibenzo-p-Dioxins and DibenzoFurans (PCDD/Fs) and dioxin-like PCBs (dl-PCBs) in sediment samples and Suspended Particulate Matter (SPM) from the Scheldt River basin and the North Sea Coast...
January 12, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29334283/effects-of-an-exercise-program-on-the-physiological-biological-and-psychological-profiles-in-patients-with-mood-disorders-a-pilot-study
#17
Mario Leone, Daniel Lalande, Linda Thériault, Émilia Kalinova, Audrey Fortin
OBJECTIVE: The objective of this study is to assess the impact of an 8-week physical training program on physiological, biological and psychological profiles in individual with mood disorders. METHODS: Seven patients participated in the study. Patients were trained twice weekly (75 min/session) for 8 weeks. The training program aimed to improve muscular and cardiorespiratory reserves as well as functional capacity. Bioassays were also measured (lipid profile, blood glucose and cortisol)...
January 15, 2018: International Journal of Psychiatry in Clinical Practice
https://www.readbyqxmd.com/read/29334126/methylated-pacs-are-more-potent-than-their-parent-compounds-a-study-on-ahr-mediated-activity-degradability-and-mixture-interactions-in-the-h4iie-luc-assay
#18
Monika M Lam, Rebecca Bülow, Magnus Engwall, John P Giesy, Maria Larsson
In this study, 26 polycyclic aromatic compounds (PACs) including native polycyclic aromatic hydrocarbons (PAHs), hydroxylated PAHs, alkylated and oxygenated PAHs and (alkylated) heterocyclic compounds were investigated for their aryl hydrocarbon receptor (AhR)-mediated potencies in the H4IIE-luc bioassay. Potential degradabilities of PACs were investigated by use of various durations of exposure (24, 48 or 72 h). Furthermore, various mixtures of PACs including PAHs, alkylated and oxygenated PAHs and heterocyclic compounds were tested for their joint AhR-mediated potency...
January 15, 2018: Environmental Toxicology and Chemistry
https://www.readbyqxmd.com/read/29332820/a-strategy-for-screening-of-%C3%AE-glucosidase-inhibitors-from-morus-alba-root-bark-based-on-the-ligand-fishing-combined-with-high-performance-liquid-chromatography-mass-spectrometer-and-molecular-docking
#19
Zhen Wang, Xiaoqing Li, Menghan Chen, Feiyan Liu, Chao Han, Lingyi Kong, Jianguang Luo
A new method based on ligand fishing combined with high-performance liquid chromatography quadrupole-time-of-flight mass spectrometer and molecular docking was established to screen α-glucosidase inhibitors from a traditional Chinese medicine Morus alba root bark. α-Glucosidase was immobilized on magnetic nanoparticles, used as a solid support to incubate with crude extract. After ligand fishing, the eluates were analyzed by high-performance liquid chromatography quadrupole-time-of-flight mass spectrometer, obtaining eleven ligands (1-4, 6-12) eventually...
April 1, 2018: Talanta
https://www.readbyqxmd.com/read/29332353/aesculetin-6-7-dihydroxycoumarin-exhibits-potent-and-selective-antitumor-activity-in-human-acute-myeloid-leukemia-cells-thp-1-via-induction-of-mitochondrial-mediated-apoptosis-and-cancer-cell-migration-inhibition
#20
Jian Gong, Wei-Guo Zhang, Xiao-Fen Feng, Mei-Juan Shao, Chao Xing
PURPOSE: The main target of the present research was to examine the antitumor properties of aesculetin in human acute myeloid leukemia cancer cells (THP-1) and peripheral blood mono-nucleated cells (PBMCs) (used as normal cell line model) along with the determination of its effects on induction of apoptosis, inhibition of cancer cell migration and changes in Bcl-2/Bax protein expressions. METHODS: MTT colorimetric bioassay was performed to study the impact of this natural compound on cytotoxicity of both cell types...
November 2017: Journal of B.U.ON.: Official Journal of the Balkan Union of Oncology
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