Read by QxMD icon Read


Barbara Król-Kogus, Khenifi Mohammed Lamine, Piotr Migas, Messaoud Boudjeniba, Mirosława Krauze-Baranowska
A new HPTLC-densitometric method for diosgenin determination in fenugreek seeds was established after optimization of the conditions for efficient saponin extraction and acid hydrolysis. Several procedures were tested, the best of which was a three-step Soxhlet extraction, followed by hydrolysis of the obtained methanolic extract with 2 mol L-1 H2SO4. Best diosgenin separation from other hydrolysis products was obtained on HPTLC Si60F254 plates u sing a mixture of n-heptane/ethyl acetate (7:3, V/V) and modified anisaldehyde as a spraying reagent...
March 1, 2018: Acta Pharmaceutica
Yunqin Cheng, Yunlu Chen, Juncheng Lu, Jianxin Nie, Yan Liu
The Fenton process is used as a tertiary treatment to remove organic pollutants from the effluent of bio-treated pharmaceutical wastewater (EBPW). The optimal and most appropriate Fenton conditions were determined by an orthogonal array test and single-factor experiments. The removal of chemical oxygen demand (COD) was influenced by the following factors in a descending order: H 2 O 2 /Fe(II) molar ratio > H 2 O 2 dosage > reaction time. Under the most appropriate Fenton conditions (H 2 O 2 /Fe(II) molar ratio of 1:1, H 2 O 2 dosage of 120 mg L -1 and reaction time of 10 min), the COD and dissolved organic carbon (DOC) were removed with efficiencies of 62 and 53%, respectively, which met the national discharge standard (GB 21903-2008) for the Lake Tai Basin, China...
February 16, 2018: Environmental Science and Pollution Research International
Haiqi Chen, Wing-Yee Lui, Dolores D Mruk, Xiang Xiao, Renshan Ge, Qingquan Lian, Will M Lee, Bruno Silvestrini, C Yan Cheng
The blood-testis barrier is a unique ultrastructure in the mammalian testis, located near the basement membrane of the seminiferous tubule that segregates the seminiferous epithelium into the basal and the adluminal (apical) compartment. Besides restricting paracellular and transcellular passage of biomolecules (e.g., paracrine factors, hormones), water, electrolytes, and other substances including toxicants and/or drugs to enter the adluminal compartment of the epithelium, the BTB is an important ultrastructure that supports spermatogenesis...
2018: Methods in Molecular Biology
Magdalena Korczynska, Mary J Clark, Celine Valant, Jun Xu, Ee Von Moo, Sabine Albold, Dahlia R Weiss, Hayarpi Torosyan, Weijiao Huang, Andrew C Kruse, Brent R Lyda, Lauren T May, Jo-Anne Baltos, Patrick M Sexton, Brian K Kobilka, Arthur Christopoulos, Brian K Shoichet, Roger K Sunahara
Subtype-selective antagonists for muscarinic acetylcholine receptors (mAChRs) have long been elusive, owing to the highly conserved orthosteric binding site. However, allosteric sites of these receptors are less conserved, motivating the search for allosteric ligands that modulate agonists or antagonists to confer subtype selectivity. Accordingly, a 4.6 million-molecule library was docked against the structure of the prototypical M 2 mAChR, seeking molecules that specifically stabilized antagonist binding. This led us to identify a positive allosteric modulator (PAM) that potentiated the antagonist N -methyl scopolamine (NMS)...
February 16, 2018: Proceedings of the National Academy of Sciences of the United States of America
Qiaoping Kong, Haizhen Wu, Lei Liu, Fengzhen Zhang, Sergei Preis, Shuang Zhu, Chaohai Wei
Polycyclic aromatic hydrocarbons (PAHs) are accumulated in the sludge collected from the coking wastewater treatment. Phenol with its efficient degradation observed in biological treatment promotes the solubility of PAHs in aqueous phase. The interaction mechanism of phenol and PAHs in aqueous and sludge phases was systematically studied in two full-scale engineering projects composed of anaerobic-oxic-oxic (A-O 1 -O 2 ) and anaerobic-oxic-hydrolytic-oxic (A-O 1 -H-O 2 ) sequences. The results showed that reasonable use of phenol facilitates solubilization of PAHs alleviating their emission problems...
February 13, 2018: Science of the Total Environment
Jun Hosogi, Rui Ohashi, Hiroshi Maeda, Kazuhiro Fujita, Junko Ushiki, Takashi Kuwabara, Yorihiro Yamamoto, Toru Imamura
We previously reported that KW-2449, (E)-1-{4-[2-(1H-Indazol-3-yl)vinyl]benzoyl}piperazine, a novel multikinase inhibitor developed for the treatment of leukemia patients, was oxidized to an iminium ion intermediate by monoamine oxidase B (MAO-B) and then converted to its oxo-piperazine form (M1) by aldehyde oxidase (AO). However, we found that the significant decrease in the pharmacologically active metabolite M1 following repeated administration of KW-2449 in primates might hamper the effectiveness of the drug...
February 16, 2018: Biopharmaceutics & Drug Disposition
Maria Myzithras, Tammy Bigwarfe, Erica Waltz, Hua Li, Jennifer Ahlberg, Irina Rybina, Sarah Low, Cynthia Hess Kenny, John Miglietta, Rachel Kroe-Barrett
AIM: The fully automated microfluidics-based Gyrolab is a popular instrument for the bioanalysis of protein therapeutics; requiring minimal sample and reagent volumes. Gyros offers affinity software for determining binding affinity in solution using a high-throughput method and miniaturized reactions. RESULTS: Using this affinity software, multiple CTGF-targeting reagents were characterized on the Gyrolab after <100% target coverage was seen in a cynomolgus pharmacokinetic/PD study dosed with anti-CTGF antibodies...
February 16, 2018: Bioanalysis
N Connor Payne, Drew R Barber, Erik L Ruggles, Robert J Hondal
Dimedone is a widely used reagent to assess the redox state of cysteine-containing proteins as it will alkylate sulfenic acid residues, but not sulfinic acid residues. While it has been reported that dimedone can label selenenic acid residues in selenoproteins, we investigated the stability, and reversibility of this label in a model peptide system. We also wondered whether dimedone could be used to detect seleninic acid residues. We used benzenesulfinic acid, benzeneseleninic acid, and model selenocysteine-containing peptides to investigate possible reactions with dimedone...
February 16, 2018: Protein Science: a Publication of the Protein Society
Roman Szostak, Michal Szostak
Resonance energies and proton affinities of N-acyl-glutarimides, compared with related twisted acyclic amides of relevance to N-C(O) cross-coupling, are reported. The data demonstrate that amidic resonance in N-acyl-glutarimides practically disappears (E R < 2.8 kcal/mol), while, intriguingly, these amides favor O-protonation despite significant twist. In some cases, N-acyl-glutarimides undergo intramolecular N- to O-acyl migration, indicative of high capacity as acylating reagents. The understanding provided for the high reactivity of N-acyl-glutarimides should facilitate the development of a broadly general N-C(O) amide activation platform...
February 16, 2018: Organic Letters
Ke Sherry Li, Liuqing Shi, Michael L Gross
Assessment of protein structure and interaction is crucial for understanding protein structure/function relationships. Compared to high-resolution structural tools, including X-ray crystallography, nuclear magnetic resonance (NMR), and cryo-EM, and traditional low-resolution methods, such as circular dichroism, UV-vis, and florescence spectroscopy, mass spectrometry (MS)-based protein footprinting affords medium-to-high resolution (i.e., regional and residue-specific insights) by taking advantage of proteomics methods focused on the primary structure...
February 16, 2018: Accounts of Chemical Research
Ting Long, Yuan Yang, Ling Peng, Zuoxiao Li
Multiple sclerosis (MS) is a chronic auto-inflammatory disease of the central nervous system (CNS) and hard to heal. This study aimed to investigate the effect of melatonin on mice with experimental autoimmune encephalomyelitis (EAE), a widely used MS model, and its potential mechanism underlying the action of MT on anti-oxidative stress. Female C57BL/6 mice were injected with MOG35-55 peptide to set up the EAE model, and for detection of the effect of melatonin (10 mg/kg i.p.) on the development and progression of EAE...
February 15, 2018: Journal of Molecular Neuroscience: MN
Caitlin A Cooper, Timothy J Doran, Arjun Challagulla, Mark L V Tizard, Kristie A Jenkins
The tools available for genome engineering have significantly improved over the last 5 years, allowing scientist to make precise edits to the genome. Along with the development of these new genome editing tools has come advancements in technologies used to deliver them. In mammals genome engineering tools are typically delivered into in vitro fertilized single cell embryos which are subsequently cultured and then implanted into a recipient animal. In avian species this is not possible, so other methods have been developed for genome engineering in birds...
2018: Journal of Animal Science and Biotechnology
Dennys Fernández, Irma Robles, Francisco J Rodríguez-Valadez, Luis A Godínez
A novel arrangement for an electro-Fenton reactor aimed to treat neutral wastewater is presented. The arrangement consists on three-compartments in series, two of them packed with a cation exchange resin and one positioned between these, containing a polarized activated carbon column where the electrochemical generation of the Fenton reagent takes place. While the hydroxyl radicals electrochemically produced in-situ, react with the pollutant species adsorbed on the activated carbon cathode, the resin compartments administrate and collect the iron cation and the hydrated proton species in alternating flow direction cycles...
February 8, 2018: Chemosphere
Luck Tosan Ereku, Ruth E Mackay, Pascal Craw, Angel Naveenathayalan, Thomas Stead, Manorharanehru Branavan, Wamadeva Balachandran
A point of care device utilising Lab-on-a-Chip technologies that is applicable for biological pathogens was designed, fabricated and tested showing sample in to answer out capabilities. The purpose of the design was to develop a cartridge with the capability to perform nucleic acid extraction and purification from a sample using a chitosan membrane at an acidic pH. Waste was stored within the cartridge with the use of sodium polyacrylate to solidify or gelate the sample in a single chamber. Nucleic acid elution was conducted using the RPA amplification reagents (alkaline pH)...
February 12, 2018: Analytical Biochemistry
Louis Jeanne-Julien, Eloi Astier, René Lai-Kuen, Grégory Genta-Jouve, Emmanuel Roulland
Reaction conditions allowing a stereoretentive cross-coupling of alkenyl sulfides with Grignard reagents using ligand-free Pd catalysis are discussed here. The presence of an adequately positioned OH function is a key feature that allows a Mg-promoted Lewis acid activation of the mercaptide leaving group. This easy to implement procedure actually relies on an in situ generation of stable Pd nanoparticles by simply mixing Pd 2 (dba) 3 , the Grignard reagent, and the vinyl sulfide cross-coupling partner in THF...
February 15, 2018: Organic Letters
Yimin Jia, Hongmei Qin, Na Wang, Zhong-Xing Jiang, Zhigang Yang
A simple, convenient method for intermolecular chlorotrifluoromethylthiolation of alkenes by using a low-cost and more abundant iron catalyst has been developed. This protocol provides a straightforward way to synthesize a variety of useful SCF 3 -containing chlorides from a wide range of alkenes, including electron-deficient, aromatic, and unactivated alkenes. Mechanistic studies indicate that this is a free radical transformation, and the stronger electrophilic trifluoromethylthiolating reagent CF 3 SCl was generated in situ under the employed conditions...
February 15, 2018: Journal of Organic Chemistry
Shekhar Kc, Prakash Basnet, Surendra Thapa, Bijay Shrestha, Ramesh Giri
We disclose a (terpy)NiBr2-catalyzed reaction protocol that regioselectively difunctionalizes unactivated olefins with tethered alkyl halides and arylzinc reagents. The reaction shows excellent functional group tolerance (such as ketones, esters, nitriles and halides) and moderate to good level of diastereoselectivity. The current cyclization/cross-coupling also tolerates molecules containing base-sensitive racemizable stereocenters, which are preserved without racemization during reaction. This cyclization/cross-coupling provides rapid access to (arylmethyl)carbo- and heterocyclic scaffolds, which occur widely as structural cores in various natural products and bioactive molecules...
February 15, 2018: Journal of Organic Chemistry
Ruben Martin, Shang-Zheng Sun
A Ni-catalyzed reductive arylation of ambiphilic a-bromo boronic esters with aryl halides is described. This platform provides an unrecognized opportunity to promote catalytic umpolung reactivity of ambiphilic reagents with aryl halides, thus unlocking a new cross-coupling strategy that complements existing technologies for the preparation of densely functionalized alkyl organometallic reagents from simple and accessible precursors.
February 15, 2018: Angewandte Chemie
Jie Cui, Jian Song, Qing Liu, Hui Liu, Yunhui Dong
The ability to introduce a nitrile group into a biologically active compound is very useful in organic synthesis, owing to the importance of nitrile groups in transformations and tuning molecular properties. To date, nucleophilic cyanation has been the most used strategy for this purpose, whilst electrophilic cyanation reactions are less developed. Recently, the electrophilic cyanation reagent N-cyano-N-phenyl-p-toluenesulfonamide (NCTS) has received increasing attention, owing to its superior properties in terms of safety and practicality...
February 15, 2018: Chemistry, An Asian Journal
C H Miller
Inhibitors are antibodies directed against haemophilia treatment products which interfere with their function. Factor VIII (FVIII) inhibitors in haemophilia A and factor IX (FIX) inhibitors in haemophilia B are significant clinically when they require a change in a patient's treatment regimen. Their persistence may increase morbidity and mortality. Multiple laboratory tests are now available for detecting and understanding inhibitors in haemophilia. Inhibitors are traditionally measured by their interference in clotting or chromogenic factor assays...
February 15, 2018: Haemophilia: the Official Journal of the World Federation of Hemophilia
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"