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Spectrophotometric estimation

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https://www.readbyqxmd.com/read/28874228/multivariate-validated-models-for-simultaneous-determination-of-ibuprofen-and-famotidine-in-the-presence-of-related-substances
#1
Eman S Elzanfaly, Hala E Zaazaa, Aya T Soudi, Maissa Y Salem
Two multivariate validated spectrophotometric methods, namely partial least-squares (PLS) and principal component regression (PCR), were developed and validated for the determination of ibuprofen and famotidine in presence of famotidine degradation products and ibuprofen impurity (4-isobutylacetophenone). A calibration set was prepared in which the two drugs together with the degradation products and impurity were modeled using a multilevel multifactor design. This calibration set was used to build the PLS and PCR models...
September 6, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28867635/effect-of-human-placental-extract-in-the-management-of-biofilm-mediated-drug-resistance-a-focus-on-wound-management
#2
Sutapa Goswami, Ratul Sarkar, Pritam Saha, Amit Maity, Tridib Sarkar, Debmalya Das, Piyali Datta Chakraborty, Subhasri Bandyopadhyay, Chandan Kumar Ghosh, Sanmoy Karmakar, Tuhinadri Sen
Management of infectious wounds, particularly chronic wounds and burn injuries, is a matter of global concern. Worldwide estimates reveal that, billions of dollars are being spent annually for the management of such chronic ailments. Evidently, bacterial biofilms pose a greater problem in the effective management of infection in chronic wounds, since most of the currently available antibiotics are unable to act on the microorganisms residing inside the protected environment of the biofilms. Accordingly, in the present study, we have attempted to evaluate the anti-biofilm properties of human placental extract (PLX) and also other virulence factors that are mediated via the quorum sensing (QS) signalling system...
September 1, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28855956/kinetic-modelling-an-integrated-approach-to-analyze-enzyme-activity-assays
#3
Jelena Boeckx, Maarten Hertog, Annemie Geeraerd, Bart Nicolai
BACKGROUND: In general, enzyme activity is estimated from spectrophotometric data, by taking the slope of the linear part of the progress curve describing the rate of change in the substrate or product monitored. As long as the substrate concentrations are sufficiently high to saturate the enzyme and, the velocity of the catalyzed reaction is directly proportional to the enzyme concentration. Under these premises, this velocity can be taken as a measure of the amount of active enzyme present...
2017: Plant Methods
https://www.readbyqxmd.com/read/28855820/in-vitro-alpha-amylase-inhibition-and-in-vivo-antioxidant-potential-of-momordica-dioica-seeds-in-streptozotocin-induced-oxidative-stress-in-diabetic-rats
#4
P Sailaja Rao, G Krishna Mohan
Momordica dioica Roxb. Commonly known as "Kakora" in Telugu, is used in the Indian traditional system of medicine for the treatment of diabetes. The aim of this study was to investigate the antidiabetic activity of methanolic extract of M. dioica seeds (MEMD) in streptozotocin (STZ) induced diabetic rats. The in vitro α-amylase inhibitory activity of the MEMD was done by spectrophotometric method. Diabetes was induced by STZ (45 mg/kg; i.p), MEMD (100 & 200 mg/kg; b.wt) and standard drug metformin (50 mg/kg; b...
September 2017: Saudi Journal of Biological Sciences
https://www.readbyqxmd.com/read/28830039/spectrophotometric-determination-of-fenoprofen-calcium-drug-in-pure-and-pharmaceutical-preparations-spectroscopic-characterization-of-the-charge-transfer-solid-complexes
#5
Marwa E Mohamed, Eman Y Z Frag, Abla A Hathoot, Essam A Shalaby
Simple, accurate and robust spectrophotometric method was developed for determination of fenoprofen calcium drug (FPC). The proposed method was based on the charge transfer (CT) reaction of FPC drug (as n-electron donor) with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), 2,4,6-trinitrophenol (picric acid, PA) or 1,2,5,8-tetrahydroxyanthraquinone (Quinalizarin, QZ) (as π-acceptors) to give highly colored charge transfer complexes. Different variables affecting the reaction such as reagent concentration, temperature and time have been carefully optimized to achieve the highest sensitivity...
August 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28826748/effects-of-exposure-to-multiple-heavy-metals-on-biochemical-and-histopathological-alterations-in-common-carp-cyprinus-carpio-l
#6
Sivakumar Rajeshkumar, Yang Liu, Junguo Ma, Hong Ying Duan, Xiaoyu Li
Heavy metals are frequently encountered as mixtures of essential and non-essential elements. Therefore, evaluation of their toxic effects individually does not offer a realistic estimate of their impact on biological processes. We studied effects of exposure to mixtures of essential and toxic metals (Cr, Cd and Pb) on biochemical, immunotoxicity level and morphological characteristics of the various tissues of a biomarker freshwater fish common carp using environmentally relevant concentrations. Fish were exposed to metal mixture through tank water for 7, 15 and 30 days, under controlled laboratory conditions...
August 18, 2017: Fish & Shellfish Immunology
https://www.readbyqxmd.com/read/28825535/simultaneous-estimation-of-ofloxacin-clotrimazole-and-lignocaine-hydrochloride-in-their-combined-ear-drop-formulation-by-two-spectrophotometric-methods
#7
Kunjan Bodiwala, Shailesh Shah, Yogini Patel, Pintu Prajapati, Bhavin Marolia, Gajanan Kalyankar
Two sensitive, accurate, and precise spectrophotometric methods have been developed and validated for the simultaneous estimation of ofloxacin (OFX), clotrimazole (CLZ), and lignocaine hydrochloride (LGN) in their combined dosage form (ear drops) without prior separation. The derivative ratio spectra method (method 1) includes the measurement of OFX and CLZ at zero-crossing points (ZCPs) of each other obtained from the ratio derivative spectra using standard LGN as a divisor, whereas the measurement of LGN at the ZCP of CLZ is obtained from the ratio derivative spectra using standard OFX as a divisor...
January 1, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28825533/analysis-of-closely-related-antioxidant-nutraceuticals-using-the-green-analytical-methodology-of-ann-and-smart-spectrophotometric-methods
#8
Mohamed A Korany, Azza A Gazy, Essam F Khamis, Marwa A A Ragab, Miranda F Kamal
Two new, simple, and specific green analytical methods are proposed: zero-crossing first-derivative and chemometric-based spectrophotometric artificial neural network (ANN). The proposed methods were used for the simultaneous estimation of two closely related antioxidant nutraceuticals, coenzyme Q10 (Q10) and vitamin E, in their mixtures and pharmaceutical preparations. The first method is based on the handling of spectrophotometric data with the first-derivative technique, in which both nutraceuticals were determined in ethanol, each at the zero crossing of the other...
January 1, 2017: Journal of AOAC International
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
#9
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
#10
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...
January 5, 2018: 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
#11
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
#12
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
#13
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
#14
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...
September 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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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