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https://read.qxmd.com/read/30771293/macro-and-microfilaricidal-activities-of-extracts-of-annona-senegalensis-and-milletia-comosa-against-onchocerca-ochengi-and-loa-loa
#1
Adela Ngwewondo, Faustin Pascal Tsague Manfo, Moses Samje, Elvis Monya, Fidelis Cho-Ngwa
Despite the efforts employed for the control of onchocerciasis, the latter has remained a significant public health problem, due mainly to the lack of safe and effective adult worm drugs and/or microfilaricides that do not kill Loa loa microfilariae (mf). Serious adverse events have been encountered after administering ivermectin to some onchocerciasis patients coinfected with Loa loa. There is therefore, an urgent need for a macro and/or microfilaricidal drug which kills Onchocerca but not L. loa microfilariae...
February 13, 2019: Experimental Parasitology
https://read.qxmd.com/read/30771108/dynamic-gas-extraction-of-iodine-in-combination-with-a-silver-triangular-nanoplate-modified-paper-strip-for-colorimetric-determination-of-iodine-and-of-iodine-interacting-compounds
#2
Marina O Gorbunova, Anastasiya A Baulina, Margarita S Kulyaginova, Vladimir V Apyari, Aleksei A Furletov, Pavel A Volkov, Vladimir E Bochenkov, Aleksandr S Starukhin, Stanislava G Dmitrienko
A method is described for sensitive and selective detection of iodine by using a paper strip modified with silver triangular nanoplates (AgTNPs). It is based on the extraction of iodine from a solution into a flow of air via dynamic gas extraction and transferring it through a reactive paper modified with AgTNPs. The interaction of AgTNPs with iodine results in a color change from blue to white. This can be visually detected and monitored by digital colorimetry. The dynamic gas extraction is highly selective for volatile compounds so that a sample pretreatment is minimal...
February 15, 2019: Mikrochimica Acta
https://read.qxmd.com/read/30769906/a-chemiluminescent-method-for-the-detection-of-h%C3%A2-o%C3%A2-and-glucose-based-on-intrinsic-peroxidase-like-activity-of-ws%C3%A2-quantum-dots
#3
Mahsa Haddad Irani-Nezhad, Javad Hassanzadeh, Alireza Khataee, Yasin Orooji
Currently, researchers are looking for nanomaterials with peroxidase-like activity to replace natural peroxidase enzymes. For this purpose, WS₂ quantum dots (WS₂ QDs) were synthesized via a solvothermal method, which improved the mimetic behavior. The resulting WS₂ QDs with a size of 1⁻1.5 nm had a high fluorescence emission, dependent on the excitation wavelength. WS₂ QDs with uniform morphology showed a high catalytic effect in destroying H₂O₂. The peroxidase-like activity of synthesized nanostructures was studied in H₂O₂ chemical and electrochemical reduction systems...
February 14, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://read.qxmd.com/read/30758882/evaluation-of-different-factors-influencing-objective-measurement-of-skin-color-by-colorimetry
#4
Tag S Anbar, Amira A Eid, Mohamed T Anbar
BACKGROUND: Objective determination of skin color has become an essential requirement in managing pigmentary disorders including vitiligo. The readings of available devices can be influenced by factors such as surrounding temperature, vasodilation/constriction, and skin surface properties. Our aim was to investigate the influence of hair color and length, skin stretching, incomplete contact of the device with the skin, and the pressure with which the device is applied to the test area on skin color determination...
February 13, 2019: Skin Research and Technology
https://read.qxmd.com/read/30746477/battery-free-skin-interfaced-microfluidic-electronic-systems-for-simultaneous-electrochemical-colorimetric-and-volumetric-analysis-of-sweat
#5
Amay J Bandodkar, Philipp Gutruf, Jungil Choi, KunHyuck Lee, Yurina Sekine, Jonathan T Reeder, William J Jeang, Alexander J Aranyosi, Stephen P Lee, Jeffrey B Model, Roozbeh Ghaffari, Chun-Ju Su, John P Leshock, Tyler Ray, Anthony Verrillo, Kyle Thomas, Vaishnavi Krishnamurthi, Seungyong Han, Jeonghyun Kim, Siddharth Krishnan, Tao Hang, John A Rogers
Wearable sweat sensors rely either on electronics for electrochemical detection or on colorimetry for visual readout. Non-ideal form factors represent disadvantages of the former, while semiquantitative operation and narrow scope of measurable biomarkers characterize the latter. Here, we introduce a battery-free, wireless electronic sensing platform inspired by biofuel cells that integrates chronometric microfluidic platforms with embedded colorimetric assays. The resulting sensors combine advantages of electronic and microfluidic functionality in a platform that is significantly lighter, cheaper, and smaller than alternatives...
January 2019: Science Advances
https://read.qxmd.com/read/30736400/colorimetric-and-ratiometric-fluorescence-dual-mode-sensing-of-glucose-based-on-carbon-quantum-dots-and-potential-uv-fluorescence-of-o-diaminobenzene
#6
Hong Zhai, Yunfeng Bai, Jun Qin, Feng Feng
A novel colorimetric and ratiometric fluorescence sensor was constructed by using carbon quantum dots (CQDs) and o-diaminobenzene (ODB). Unlike ODB by itself, ODB oxide (oxODB) not only emits fluorescence, but also produces ultraviolet (UV) absorption. Therefore, on the basis of the potential optical properties of ODB, glucose oxidase (Gox) and horseradish peroxidase (HRP) were introduced into a CQDs⁻ODB system for the quantitative oxidation of ODB. When glucose is present, it is oxidized by oxygen under the catalytic action of its oxidase to form hydrogen peroxide...
February 7, 2019: Sensors
https://read.qxmd.com/read/30721100/the-antagonistic-effect-of-tamoxifen-against-d-galactosamine-lipopolysaccharide-induced-acute-liver-failure-is-associated-with-reactivation-of-hepatic-nuclear-factor-%C3%AE%C2%BAb
#7
Liping Liu, Yongsheng Zhao, Yan Lin, Rongshan Zhang, Shi Luo, Ping Ye, Mansheng Luo
CONTEXT: Tamoxifen (TAM) ameliorates D-galactosamine/lipopolysaccharide (Gal/LPS)-induced acute liver failure (ALF) through its antioxidative effect; thus, this study was designed to determine whether the effectiveness of TAM is related to nuclear factor-κB (NF-κB) reactivation. MATERIALS AND METHODS: Experimental mice were injected with TAM once daily for 3 consecutive days intraperitoneally (i.p). Twelve hours after pretreatment, Gal/LPS was given to mice (i...
February 5, 2019: Immunopharmacology and Immunotoxicology
https://read.qxmd.com/read/30697060/evaluation-of-the-efficacy-of-a-new-hyaluronic-acid-gel-on-dynamic-and-static-wrinkles-in-volunteers-with-moderate-aging-photoaging
#8
Adele Sparavigna, Beatrice Tenconi, Andrea Maria Giori, Gilberto Bellia, Laura La Penna
Purpose: Aim of the study was to determine both clinically and by noninvasive instrumental evaluations the efficacy, tolerability and the duration of the effects of a new hyaluronic acid (HA) gel in human volunteers with moderate aging/photoaging. Patients and methods: Eighteen volunteers (35-55 years) were enrolled in this single-center study. The subjects underwent five visits. The first visit was at baseline to determine the adherence to the inclusion criteria, followed by the first injection of the HA-based study product, and the second visit was at 48 hours after the injection...
2019: Clinical, Cosmetic and Investigational Dermatology
https://read.qxmd.com/read/30693728/-effects-of-different-processing-methods-on-water-soluble-polysaccharide-contents-and-monosaccharide-compositions-in-cervi-cornu-pantotrichum
#9
Ruize Gong, Yanhua Wang, Yuli Qi, Lixue Chen, Shanshan Li, Yinshi Sun
The water-soluble polysaccharides in antler velvet were extracted by water extraction and alcohol precipitation. The content was determined by a phenol-sulfuric acid colorimetry. After hydrolysis and derivatization, the various monosaccharide compositions of water-soluble polysaccharides from different parts of the antler velvet after different processing methods were analyzed by ultra high performance liquid chromatography (UPLC). The results showed that the water-soluble polysaccharide contents in wax slices, powder slices, gauze slices and bone slices of the boiled antler velvet were 1...
February 8, 2019: Se Pu, Chinese Journal of Chromatography
https://read.qxmd.com/read/30685586/biosynthesis-of-iron-oxide-nanoparticles-using-leaf-extract-of-ruellia-tuberosa-antimicrobial-properties-and-their-applications-in-photocatalytic-degradation
#10
Seerangaraj Vasantharaj, Selvam Sathiyavimal, Palanisamy Senthilkumar, Felix LewisOscar, Arivalagan Pugazhendhi
Green synthesis of nanoparticles is one of the promising, ecofriendly and safer methods. Utilizing plant sources as reducing agents will replace the use of toxic chemicals for nanoparticle synthesis. In the present study FeONPs were synthesized using Ruellia tuberosa (RT) leaf aqueous extract, further characterization of FeONPs was performed using UV-vis spectroscopy analysis showing visible peak at 405 nm. The Fourier transform infrared spectroscopy (FTIR) proved the presence of Fe metallic ions. The structural characteristic using Field emission scanning electron microscopy with energy dispersive x-ray spectroscopy (FESEM-EDX) and Transmission electron microscopy (TEM) analysis revealed hexagonal nanorods with agglomeration...
December 28, 2018: Journal of Photochemistry and Photobiology. B, Biology
https://read.qxmd.com/read/30684881/application-of-functionalized-silver-nanoparticles-as-a-biochemical-sensor-for-selective-detection-of-lysozyme-protein-in-milk-sample
#11
Kamlesh Shrivas, Nidhi Nirmalkar, Manas Kanti Deb, Khemchand Dewangan, Jayant Nirmalkar, Suneel Kumar
Silver nanoparticles (AgNPs) functionalized with glutamic acid (GA) was used as a biochemical sensing probe in colorimetry for detection of lysozyme protein in milk samples. The method is based on the color change of AgNPs/GA from yellow to reddish-yellow differentiated with naked eyes for qualitative determination and red shift of localized surface plasmon resonance (LSPR) absorption signal intensity of AgNPs/GA in visible region used for quantitative determination of lysozyme. The control experiments were performed to demonstrate the electrostatic force of interactions between AgNPs/GA and protein molecule...
January 16, 2019: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://read.qxmd.com/read/30682715/oxytocin-facilitates-the-proliferation-migration-and-osteogenic-differentiation-of-human-periodontal-stem-cells-in-vitro
#12
Bin Ge, Hongrui Liu, Qianyu Liang, Lingling Shang, Ting Wang, Shaohua Ge
OBJECTIVE: To explore the effect of oxytocin (OT) on the proliferation, migration, and osteogenic differentiation of periodontal ligament stem cells (PDLSCs) in vitro. DESIGN: PDLSCs were obtained by limiting dilution method. Immunofluorescence (IF), cell-counting kit-8 (CCK8), cell migration assay, Alizarin Red S staining, cetylpyridinium chloride (CPC) colorimetry, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis were used to examine the effect of OT on oxytocin receptor (OTR) expression, cell proliferation, migration and osteogenic differentiation of PDLSCs...
January 19, 2019: Archives of Oral Biology
https://read.qxmd.com/read/30673854/colorimetric-and-fluorometric-dual-channel-detection-of-%C3%AE-fetoprotein-based-on-the-use-of-zns-cdte-hierarchical-porous-nanospheres
#13
Dong Zhu, Yue Hu, Xiao-Jing Zhang, Xiao-Tong Yang, Ying-Ying Tang
An immunoassay is described for either colorimetric and fluorometric determination of the cancer biomarker α-fetoprotein (AFP). It is making use of ZnS nanospheres modified with CdTe quantum dots (QDs). These display strong fluorescence due to the enrichment of the QDs onto the porous ZnS nanospheres. In this assay, the release of millions of zinc(II) ions can be triggered to form a purple complex (with an absorption maximum at 571 nm) on addition of the reagent 2-(5-nitro-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino) phenol...
January 23, 2019: Mikrochimica Acta
https://read.qxmd.com/read/30669784/-interleukin-17-mediated-inflammation-promotes-nonalcoholic-fatty-liver-disease-in-mice-with-regulation-of-m1-type-macrophage-polarization
#14
Y Yang, C Y Han, Q B Guan, S L Ruan
Objective: To study the mechanism of interleukin (IL)-17 in mice with non-alcoholic fatty liver disease for promoting M1-type macrophage polarization to exacerbate liver inflammation, and to provide references for the mechanism of NAFLD occurrence and development. Methods: A mouse model of NAFLD was constructed by high-fat diet. Mice were divided into control group, model group, IL-17 group, and anti IL-17 group. Histopathological changes of the liver were observed by HE staining. The serum levels of ALT and AST in peripheral blood of mice was detected by chemical colorimetry...
December 20, 2018: Zhonghua Gan Zang Bing za Zhi, Zhonghua Ganzangbing Zazhi, Chinese Journal of Hepatology
https://read.qxmd.com/read/30669352/arsenic-monitoring-in-water-by-colorimetry-using-an-optimized-leucomalachite-green-method
#15
Annija Lace, David Ryan, Mark Bowkett, John Cleary
Arsenic contamination of drinking water is a global concern. Standard laboratory methods that are commonly used for arsenic detection in water, such as atomic absorption spectroscopy and mass spectroscopy, are not suitable for mass monitoring purposes. Autonomous microfluidic detection systems combined with a suitable colorimetric reagent could provide an alternative to standard methods. Moreover, microfluidic detection systems would enable rapid and cost efficient in situ monitoring of water sources without the requirement of laborious sampling...
January 18, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://read.qxmd.com/read/30648216/nanomaterial-based-optical-and-electrochemical-techniques-for-detection-of-methicillin-resistant-staphylococcus-aureus-a-review
#16
REVIEW
Atal A S Gill, Sima Singh, Neeta Thapliyal, Rajshekhar Karpoormath
Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for a number of life-threatening complications in humans. Mutations in the genetic sequence of S. aureus due to the presence of certain genes results in resistance against β-lactamases. Thus, there is an urgent need for developing highly sensitive techniques for the early detection of MRSA to counter the rise in resistant strains. This review (142 refs.) extensively covers literature reports on nanomaterial-based optical and electrochemical sensors from the year 1983 to date, with particularly emphasis on recent advances in electrochemical sensing (such as voltammetry and impedimetric) and optical sensing (such as colorimetry and fluorometry) techniques...
January 16, 2019: Mikrochimica Acta
https://read.qxmd.com/read/30642481/solid-phase-colorimetric-determination-of-iodine-in-food-grade-salt-using-polymethacrylate-matrix
#17
Nataliya A Gavrilenko, Dmitrii A Fedan, Nadezhda V Saranchina, Mikhail A Gavrilenko
A novel colorimetric sensor has been proposed for sensitive and accurate detection of iodine forms using polymethacrylate matrix, which also has the outlook for use with samples without pre-treatment and is suitable to fit in a portable instrument for in situ iodine analysis. This determination method is based on interaction of polymethacrylate matrix with iodine forms followed by measurement of absorbance at 370 nm. The principle of this colorimetric sensor is not ordinary colorimetry, but a new colorimetric strategy that combines solid phase extraction and spectrophotometric determination of a target substance following completion of the color change processes...
May 15, 2019: Food Chemistry
https://read.qxmd.com/read/30638713/disassociation-of-glutamate-from-%C3%AE-aminobutyric-acid-by-zinc-acetate-assisted-differential-precipitation-dissolution-application-to-the-quantification-of-%C3%AE-aminobutyric-acid
#18
Yuanhong Chen, Kunpeng Chang, Xi Xie, Xiaohua Liu, Mengya Jia, Lijuan Nie, Haixing Li, Shuixing Wang
γ-aminobutyric acid (GABA) is a key physiologically active molecule in organisms. Separation of glutamate from its decarboxylated product GABA has been vigorously pursued. The interaction between these two compounds severely hindered their disassociation. Herein, we present a new strategy, termed zinc acetate-assisted differential precipitation/dissolution (ZA-DPD), for the removal of glutamate by step by step recovering pure GABA solution and discarding pure glutamate pellet, essentially attributed to the use of two core reagents (zinc acetate-assisted glutamate-precipitating reagent, and glutamate-rejecting reagent)...
January 3, 2019: Journal of Chromatography. A
https://read.qxmd.com/read/30631938/colorimetric-and-electrochemical-dual-thrombin-assay-based-on-the-use-of-a-platinum-nanoparticle-modified-metal-organic-framework-type-fe-mil-88-acting-as-a-peroxidase-mimic
#19
Ting Cheng, Xiang Li, Peng Huang, Han Wang, Meixia Wang, Wenming Yang
An electrochemical and colorimetric dual-readout method is described for the determination of thrombin. A platinum nanoparticle (Pt NP) modified metal organic framework (MOF) acts as a peroxidase (POx) mimic that causes the formation of a blue product from 3,3',5,5'-tetramethylbenzidine (TMB) and hydrogen peroxide, with an absorption maximum at 650 nm. In addition, gold nanoparticles enrich initiators that trigger the hybridization chain reaction for dual signal amplification to generate an electrochemical current typically measured at 0...
January 10, 2019: Mikrochimica Acta
https://read.qxmd.com/read/30630806/effect-of-donepezil-hydrochloride-aerobic-exercise-training-on-learning-and-memory-and-its-mechanism-of-action-in-an-alzheimer-s-disease-rat-model
#20
Nan Jiangbo, Zhang Liyun
This study was designed to explore the combined effect of donepezil hydrochloride and aerobic exercise training on learning and memory and to check its mechanism of action in an Alzheimer's disease (AD). Thirty rats were randomly divided into normal control group, model group and donepezil hydrochloride combined with aerobic exercise training group (n=10). Amyloid β-protein (Aβ1-40) was injected into rats to establish an elderly AD model. After 4 weeks of administration, changes in the spatial learning and memory of rats were tested in the Morris water maze...
November 2018: Pakistan Journal of Pharmaceutical Sciences
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