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Spectrophotometric estimation

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https://www.readbyqxmd.com/read/28780456/synthesis-single-crystal-dna-interaction-spectrophotometric-and-spectroscopic-characterization-of-the-hydrogen-bonded-charge-transfer-complex-of-2-aminopyrimidine-with-%C3%AF-acceptor-chloranilic-acid-at-different-temperature-in-acetonitrile
#1
Zulkarnain, Lal Miyan, Afaq Ahmad, Md Fazle Alam, Hina Younus
The charge transfer (CT) interaction of 2-aminopyrimidine (AP) with chloranilic acid (CLA) as π-acceptor was investigated spectrophotometrically in acetonitrile at different temperatures in the range of 25-50°C. The 1:1 stoichiometry of the synthesized CT complex was detected using straight line method. Benesi-Hildebrand equation was used to determine the association constant (KCT), molar extinction coefficient (ε) and other physical parameters. Various thermodynamics parameters such as enthalpy (ΔH), entropy (ΔS) and free energy (ΔG) were determined using UV-Visible spectrophotometry in acetonitrile at different temperatures...
July 4, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28759854/analytical-method-development-and-validation-of-spectrofluorimetric-and-spectrophotometric-determination-of-some-antimicrobial-drugs-in-their-pharmaceuticals
#2
F Ibrahim, M E K Wahba, G Magdy
In this study, three novel, sensitive, simple and validated spectrophotometric and spectrofluorimetric methods have been proposed for estimation of some important antimicrobial drugs. The first two methods have been proposed for estimation of two important third-generation cephalosporin antibiotics namely, cefixime and cefdinir. Both methods were based on condensation of the primary amino group of the studied drugs with acetyl acetone and formaldehyde in acidic medium. The resulting products were measured by spectrophotometric (Method I) and spectrofluorimetric (Method II) tools...
July 24, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28758414/modulation-of-n-methyl-d-aspartate-receptors-in-isolated-rat-heart
#3
Ivan M Srejovic, Vladimir I Zivkovic, Tamara R Nikolic, Nevena Jeremic, Isidora Stojic, Jovana Jeremic, Dragan Djuric, Vladimir Jakovljevic
Considering the limited data about the role of N-methyl-D-aspartate receptors (NMDA-R) in cardiovascular system and heart, the aim of the present study was to examine the effects of NMDA and DL-homocysteine thiolacotne (DL-Hcy TLHC), alone and in combinations with glycine, memantine and ifenprodil, in the isolated rat heart. The hearts of Wistar albino rats were retrogradely perfused according to the Langendorff technique at a constant perfusion pressure. The experimental protocol for all experimental groups included the stabilization period, application of estimated substance in duration of 5 minutes, followed by wash-out period in duration of 10 minutes...
July 30, 2017: Canadian Journal of Physiology and Pharmacology
https://www.readbyqxmd.com/read/28738622/a-flow-based-procedure-exploiting-the-lab-in-syringe-approach-for-the-determination-of-ester-content-in-biodiesel-and-diesel-biodiesel-blends
#4
Samara Soares, Wanessa R Melchert, Fábio R P Rocha
The ester content is an important parameter to be monitored in biodiesel for evaluation of the transesterification reaction yield and for assessing the purity of the final product. This is also a relevant quality parameter in diesel/biodiesel blends to avoid frauds, because legislation establishes a minimum amount of biodiesel to be added to diesel. The official method EN14103 requires the addition of an alternative internal standard (methyl nonadecanoate) for analysis of biodiesel from bovine tallow because the methyl heptadecanoate is found in high amounts in this product...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28735060/individual-roles-of-brain-and-serum-alcohol-dehydrogenase-isoforms-in-regulation-of-alcohol-consumption-in-spf-wistar-rats
#5
Vsevolod V Pavshintsev, Nikita A Mitkin, Olga Y Frolova, Ekaterina A Kushnir, Olga A Averina, Maxim L Lovat
Alcohol dehydrogenases (ADH) are key enzymes of ethanol metabolism that mediate its oxidation to acetaldehyde. ADHs are also able to oxidize some types of neurotransmitters such as dopamine, serotonin and norepinephrine. Increased level of ADHs activity, induced by chronic alcohol consumption, is presumably associated with disturbed neurotransmitters metabolism that leads to stable alcohol craving. As earlier reported, intraperitoneal administration of 4-methilpirasole (non-specific inhibitor of ADHs) has shown to provide a short-term anti-alcoholic effect, but individual roles of ADH isoforms in this process were still unclear...
July 20, 2017: Physiology & Behavior
https://www.readbyqxmd.com/read/28735047/sesamol-exhibits-potent-antimycobacterial-activity-underlying-mechanisms-and-impact-on-virulence-traits
#6
Sandeep Hans, Sharda Sharma, Saif Hameed, Zeeshan Fatima
OBJECTIVES: Novel strategies to overcome multidrug resistance (MDR) in Tuberculosis (TB) still remain a concern. Usage of natural compounds nowadays to surmount the increasing burden of MDR-TB has shown promising results. The aim of this study was to evaluate the antimycobacterial potential of sesamol (Ses) a natural phenolic compound against Mycobacterium smegmatis, a surrogate for MTB and its underlying mechanism of action along with its effect on mycobacterial virulence traits. METHODS: Cell surface phenotypes were estimated microscopically and spectrophotometrically respectively...
July 19, 2017: Journal of Global Antimicrobial Resistance
https://www.readbyqxmd.com/read/28718676/selenium-zinc-copper-cu-zn-ratio-and-total-antioxidant-status-in-the-serum-of-vitiligo-patients-treated-by-narrow-band-ultraviolet-b-phototherapy
#7
Marta Wacewicz, Katarzyna Socha, Jolanta Soroczyńska, Marek Niczyporuk, Piotr Aleksiejczuk, Jolanta Ostrowska, Maria H Borawska
BACKGROUND: Vitiligo is a chronic, depigmenting skin disorder, whose pathogenesis is still unknown. Narrow band ultraviolet-B (NB-UVB) is now one of the most widely used treatment of vitiligo. It was suggested that trace elements may play a role in pathogenesis of vitiligo. AIM: The aim of this study was to estimate the concentration of selenium (Se), zinc (Zn), copper (Cu) and Cu/Zn ratio as well as total antioxidant status (TAS) in the serum of patients with vitiligo...
August 1, 2017: Journal of Dermatological Treatment
https://www.readbyqxmd.com/read/28712138/hematologic-reference-intervals-and-age-effect-in-european-strigiformes
#8
Susana Agusti Montolio, Rafael Molina López, Carolyn Cray, Santiago Lavín González, Olga Nicolás Francisco, Ignasi Marco Sánchez, Encarna Casas-Díaz, Rafaela Cuenca Valera
BACKGROUND: The clinical importance of hematologic testing in avian veterinary medicine is reflected in the increasing number of studies for the establishment of hematologic RIs of Strigiformes and other species. Age is an important physiologic factor in birds and the effect on hematology variable should be understood. OBJECTIVES: The objective of this study was to determine baseline data of hematologic variables in 5 species of Iberian Strigiformes in different age classes...
July 16, 2017: Veterinary Clinical Pathology
https://www.readbyqxmd.com/read/28643762/serum-butyrylcholinesterase-and-zinc-in-breast-cancer
#9
Rupesh Kumar, Sairoz Razab, Krishnananda Prabhu, Satadru Ray, Bhanu Prakash
CONTEXT: Even though, a large number of serological, molecular markers have been proposed for breast cancer screening, most of them lack specificity, sensitivity, prognostic value, and cost effectiveness. Butyrylcholinesterase (BChE) and its genes are aberrantly expressed in a variety of human cancers. It has-been linked to tumorigenesis, cell proliferation, and cell differentiation. Zinc (Zn) is a cofactor for superoxide dismutase, an enzyme that protects cellular components against free radical-induced damage and carcinogenesis...
April 2017: Journal of Cancer Research and Therapeutics
https://www.readbyqxmd.com/read/28629725/relationship-between-histopathological-status-of-the-helicobacter-pylori-infected-patients-and-proteases-of-h-%C3%A2-pylori-in-isolates-carrying-diverse-virulence-genotypes
#10
Somayyeh Gharibi, Tahereh Falsafi, Masoud Alebouyeh, Nastaran Farzi, Farzam Vaziri, Mohamad Reza Zali
Helicobacter pylori is the main cause of several gastroduodenal diseases in Humans. Among various virulence factors of H. pylori, proteases may also be involved in its pathogenicity. In this study, relationship between proteolytic activity of H. pylori strains and histopathological changes of the stomach was investigated in the patients infected with strains carrying diverse virulence factors. H. pylori strains were isolated from the biopsies of 116 patients who referred to hospital for their gastroduodenal disorders, in Tehran, Iran...
June 16, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28554128/mechanistic-insights-into-the-effects-of-quercetin-and-or-glp-1-analogue-liraglutide-on-high-fat-diet-streptozotocin-induced-type-2-diabetes-in-rats
#11
Hanaa H Gaballah, Soha S Zakaria, Shorouk E Mwafy, Nahid M Tahoon, Abla M Ebeid
BACKGROUND: The development of complementary treatment strategies that focuses on achieving a balance between adaptive and apoptotic unfolded protein response (UPR), enhancing endoplasmic reticulum (ER) homeostasis, and thus preserving β cell mass and function is particularly warranted. AIM: This study was designed to investigate the effectiveness of the combined treatment by Quercetin (QUE) and Liraglutide (LIRA) in modulating hyperglycemia, insulin-insensitivity, UPR/ER stress markers, apoptosis, oxidative stress and inflammation using a high-fat diet/streptozotocin -induced type 2 diabetic rat model...
August 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28542879/catalase-cat-promoter-and-5-utr-genetic-variants-lead-to-its-altered-expression-and-activity-in-vitiligo
#12
M S Mansuri, S D Jadeja, M Singh, N C Laddha, M Dwivedi, R Begum
BACKGROUND: Oxidative stress is considered to be the initial event during the course of vitiligo. Catalase is mainly involved in the defense against oxidizing agents in the cell through detoxifying H2 O2 . OBJECTIVES: Aims of the present study were 1) to assess the erythrocyte catalase activity and LPO levels, as well as CAT mRNA expression in skin and blood; 2) to investigate CAT promoter rs7943316, rs1001179; 5'-UTR rs1049982 and exon (rs17886350, rs11032709, rs17880442, rs35677492) polymorphisms and; 3) to perform genotype-phenotype/ haplotype correlation analyses, in vitiligo patients and controls from Gujarat...
May 25, 2017: British Journal of Dermatology
https://www.readbyqxmd.com/read/28539718/azorella-compacta-infusion-activates-human-immune-cells-and-scavenges-free-radicals-in-vitro
#13
Lenka Tůmová, Zuzana Dučaiová, José Cheel, Ivan Vokřál, Beatriz Sepúlveda, Doris Vokurková
BACKGROUND: Azorella compacta is traditionally used in the form of tea (infusion), in the Andean region of South America, to treat various chronic diseases. However, the health-promoting properties of this herbal tea have not yet been extensively explored. MATERIALS AND METHODS: The free radical scavenging activity of A. compacta infusion (ACI) was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and superoxide anion radical assays. The activation of immune cells by ACI, as determined by cell surface cluster of differentiation 69 expression, was measured by flow cytometry...
April 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/28521827/antioxidant-activity-acetylcholinesterase-inhibitory-potential-and-phytochemical-analysis-of-sarcocephalus-latifolius-sm-bark-used-in-traditional-medicine-in-sudan
#14
Alsiddig Osama, Sufyan Awadelkarim, Amna Ali
BACKGROUND: Sarcocephalus latifolius is used as a traditional medicine for curing many diseases in Sudan. The main objective of the current study was to determine the antioxidant activity and acetylcholinesterase inhibition (AChEI) of S. latifolius, and to estimate its total phenolic and flavonoid contents. METHODS: Antioxidant activity of the tested plant extracts was carried out by determining their ability to scavenge the 2,2-diphenyl-1-picryl hydrazyl (DPPH) free radical...
May 18, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28505111/effects-of-mead-wort-heat-treatment-on-the-mead-fermentation-process-and-antioxidant-activity
#15
Sławomir Czabaj, Joanna Kawa-Rygielska, Alicja Z Kucharska, Jarosław Kliks
The effects of mead wort heat treatment on the mead fermentation process and antioxidant activity were tested. The experiment was conducted with the use of two different honeys (multiflorous and honeydew) collected from the Lower Silesia region (Poland). Heat treatment was performed with the use of a traditional technique (gently boiling), the more commonly used pasteurization, and without heat treatment (control). During the experiment fermentation dynamics were monitored using high performance liquid chromatography with refractive index detection (HPLC-RID)...
May 14, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28501974/proteolytic-activities-in-cortex-of-apical-parts-of-vicia-faba-ssp-minor-seedling-roots-during-kinetin-induced-programmed-cell-death
#16
Andrzej Kaźmierczak, Magdalena Doniak, Anita Kunikowska
Programmed cell death (PCD) is a crucial process in plant development. In this paper, proteolytically related aspects of kinetin-induced PCD in cortex cells of Vicia faba ssp. minor seedlings were examined using morphological, fluorometric, spectrophotometric, and fluorescence microscopic analyses. Cell viability estimation after 46 μM kinetin treatment of seedling roots showed that the number of dying cortex cells increased with treatment duration, reaching maximum after 72 h. Weight of the apical root segments increased with time and was about 2...
May 13, 2017: Protoplasma
https://www.readbyqxmd.com/read/28475326/spectrophotometric-analysis-of-phenolic-compounds-in-grapes-and-wines
#17
REVIEW
Jose Luis Aleixandre-Tudo, Astrid Buica, Helene Nieuwoudt, Jose Luis Aleixandre, Wessel du Toit
Phenolic compounds are of crucial importance for red wine color and mouthfeel attributes. A large number of enzymatic and chemical reactions involving phenolic compounds take place during winemaking and aging. Despite the large number of published analytical methods for phenolic analyses, the values obtained may vary considerably. In addition, the existing scientific knowledge needs to be updated, but also critically evaluated and simplified for newcomers and wine industry partners. The most used and widely cited spectrophotometric methods for grape and wine phenolic analysis were identified through a bibliometric search using the Science Citation Index-Expanded (SCIE) database accessed through the Web of Science (WOS) platform from Thompson Reuters...
May 24, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28460317/simultaneous-determination-of-the-brand-new-two-drug-combination-for-the-treatment-of-hepatitis-c-sofosbuvir-ledipasvir-using-smart-spectrophotometric-methods-manipulating-ratio-spectra
#18
Maya S Eissa
In this work, various sensitive and selective spectrophotometric methods were first introduced for the simultaneous determination of sofosbuvir and ledipasvir in their binary mixture without preliminary separation. Ledipasvir was determined simply by zero-order spectrophotometric method at its λmax=333.0nm in a linear range of 2.5-30.0μg/ml without any interference of sofosbuvir even in low or high concentrations and with mean percentage recovery of 100.05±0.632. Sofosbuvir can be quantitatively estimated by one of the following smart spectrophotometric methods based on ratio spectra developed for the resolution of the overlapped spectra of their binary mixture; ratio difference spectrophotometric method (RD) by computing the difference between the amplitudes of sofosbuvir ratio spectra at 228nm and 270nm, first derivative (DD(1)) of ratio spectra by measuring the sum of amplitude of trough and peak at 265nm and 277nm, respectively, ratio subtraction (RS) spectrophotometric method in which sofosbuvir can be successfully determined at its λmax=261...
April 20, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28452015/biodegradation-of-ciprofloxacin-by-white-rot-fungus-pleurotus-ostreatus
#19
Sushil Kumar Singh, Robinka Khajuria, Loveleen Kaur
Unrestricted and reckless use of antibiotics has resulted in their accumulation in environment. This, in turn, has led to the emergence of multiple drug-resistant microbes. The present study focuses on degradation of ciprofloxacin (CIP) by an edible white rot fungus Pleurotus ostreatus. Effect of CIP was determined on radial growth and biomass of P. ostreatus. Titrimetric and spectrophotometric assays were carried out to assess the degrading potential of P. ostreatus towards CIP. It was found that CIP has a stimulatory effect on growth and enzyme activity of P...
May 2017: 3 Biotech
https://www.readbyqxmd.com/read/28443587/role-of-trace-elements-for-oxidative-status-and-quality-of-human-sperm
#20
Galina Nenkova, Lubomir Petrov, Albena Alexandrova
BACKGROUND: Oxidative stress affects negatively the sperm quality. For maintaining the pro/antioxidative balance, some metal ions (e.g. copper, zinc, iron, selenium), which are co-factors of the antioxidant enzymes, are essential. However, iron and copper could act as prooxidants inducing oxidative damage of spermatozoa. AIMS: This study aims to reveal a possible correlation between the concentrations of some metal ions (iron, copper, zinc, and selenium) in human seminal plasma, oxidative stress, assessed by malondialdehyde (MDA) and total glutathione (tGSH) levels, and semen quality, assessed by the parameters count, motility, and morphology...
April 6, 2017: Balkan Medical Journal
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