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Spectrophotometric estimation

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https://www.readbyqxmd.com/read/28159256/variability-in-spectrophotometric-pyruvate-analyses-for-predicting-onion-pungency-and-nutraceutical-value
#1
Vanesa H Beretta, Florencia Bannoud, Marina Insani, Claudio R Galmarini, Pablo F Cavagnaro
Onion pyruvate concentration is used as a predictor of flavor intensity and nutraceutical value. The protocol of Schwimmer and Weston (SW) (1961) is the most widespread methodology for estimating onion pyruvate. Anthon and Barret (AB) (2003) proposed modifications to this procedure. Here, we compared these spectrophotometry-based procedures for pyruvate analysis using a diverse collection of onion cultivars. The SW method always led to over-estimation of pyruvate levels in colored, but not in white onions, by up to 65%...
June 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28153358/synthesis-of-new-chromeno-carbamodithioate-derivatives-and-preliminary-evaluation-of-their-antioxidant-activity-and-molecular-docking-studies
#2
Sampath Kumar Bandari, Bal Raju Kammari, Jyothi Madda, Nagaiah Kommu, Arunapriya Lakkadi, Srimai Vuppala, Parthasarathy Tigulla
New chromeno carbamodithioates (7a-i), have been synthesized from 2, 3-dimethyl-7-(oxiran-2-ylmethoxy)-4H-chromen-4-one (5), carbondisulphide and commercially available acyclic and cyclic secondary amines in acetonitrile with good to excellent yields. The free radical scavenging activity of novel chromone-carbamodithioate analogues was quantitatively estimated by spectrophotometric method. Whereas, molecular docking studies were performed with the active site of cyclooxygenase-2 to identify hydrogen bonding, hydrophobic and ionic interactions between protein and ligands...
January 21, 2017: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/28138346/effect-of-high-carbohydrate-diet-on-elongase-and-desaturase-activity-and-accompanying-gene-expression-in-rat-s-liver
#3
Jagoda Drąg, Anna Goździalska, Małgorzata Knapik-Czajka, Anna Gawędzka, Katarzyna Gawlik, Jerzy Jaśkiewicz
BACKGROUND: Hepatic fatty acids (FAs) are modified through different metabolic pathways including elongation and desaturation. These processes are catalyzed by elongases and desaturases, respectively. Glucose, by transcription factors, regulates these processes. The aim of the study was to evaluate the influence of high carbohydrate diet (68%) on the expression of elongase (Elovl-2, Elovl-5, and Elovl-6) and desaturase (∆5D, ∆6D, Scd 1, Scd 2) genes and the activity of the enzymes...
2017: Genes & Nutrition
https://www.readbyqxmd.com/read/28107044/quercetin-attenuates-cell-survival-inflammation-and-angiogenesis-via-modulation-of-akt-signaling-in-murine-t-cell-lymphoma
#4
Akhilendra Kumar Maurya, Manjula Vinayak
AKT signaling is important to maintaining normal physiology. Hyperactivation of AKT signaling is frequent in cancer, which maintains a high oxidative state in a tumor microenvironment that is needed for tumor adaptation. Therefore, antioxidants are proposed to exhibit anticancer properties by interfering with the tumor microenvironment. Quercetin is an ubiquitous bioactive antioxidant rich in vegetables and beverages. The present study aimed to analyze cancer preventive property of quercetin in ascite cells of Dalton's lymphoma-bearing mice...
January 20, 2017: Nutrition and Cancer
https://www.readbyqxmd.com/read/28098944/validation-of-a-smartphone-based-point-of-care-hemoglobin-assay-for-use-in-dogs
#5
Kate S Farrell, Phillip L Chapman, Lauren A Sullivan
OBJECTIVE: To validate a smartphone-based spectrophotometric assay for point-of-care (POC) measurement of hemoglobin (Hgb) concentration against the standard measurement method in dogs without increases in serum lipemia, hemolysis, or bilirubin. DESIGN: Prospective observational study. SETTING: University teaching hospital. ANIMALS: One hundred thirty-nine dogs that had a CBC and corresponding biochemical profile submitted to the clinical pathology laboratory...
January 18, 2017: Journal of Veterinary Emergency and Critical Care
https://www.readbyqxmd.com/read/28074209/cu-i-and-ag-i-complex-formation-with-the-hydrophilic-phosphine-1-3-5-triaza-7-phosphadamantane-in-different-ionic-media-how-to-estimate-the-effect-of-a-complexing-medium
#6
Francesco Endrizzi, Plinio Di Bernardo, Pier Luigi Zanonato, Francesco Tisato, Marina Porchia, Abdirisak Ahmed Isse, Andrea Melchior, Marilena Tolazzi
The complexes of Cu(i) and Ag(i) with 1,3,5-triaza-7-phosphadamantane (PTA) are currently studied for their potential clinical use as anticancer agents, given the cytotoxicity they exhibited in vitro towards a panel of several human tumor cell lines. These metallodrugs are prepared in the form of [M(PTA)4](+) (M = Cu(+), Ag(+)) compounds and dissolved in physiological solution for their administration. However, the nature of the species involved in the cytotoxic activity of the compounds is often unknown. In the present work, the thermodynamics of formation of the complexes of Cu(i) and Ag(i) with PTA in aqueous solution is investigated by means of potentiometric, spectrophotometric and microcalorimetric methods...
January 11, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28060334/measuring-nitrite-and-nitrate-metabolites-in-the-nitric-oxide-pathway-in-biological-materials-using-the-chemiluminescence-method
#7
Barbora Piknova, Ji Won Park, Katelyn S Cassel, Cameron N Gilliard, Alan N Schechter
Nitric oxide (NO) is one of the main regulator molecules in vascular homeostasis and also a neurotransmitter. Enzymatically produced NO is oxidized into nitrite and nitrate by interactions with various oxy-heme proteins and other still not well known pathways. The reverse process, reduction of nitrite and nitrate into NO had been discovered in mammals in the last decade and it is gaining attention as one of the possible pathways to either prevent or ease a whole range of cardiovascular, metabolic and muscular disorders that are thought to be associated with decreased levels of NO...
December 25, 2016: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28025107/apigenin-potentiates-the-antitumor-activity-of-5-fu-on-solid-ehrlich-carcinoma-crosstalk-between-apoptotic-and-jnk-mediated-autophagic-cell-death-platforms
#8
Hanaa H Gaballah, Rasha A Gaber, Darin A Mohamed
BACKGROUND: Although 5- Fluorouracil (5-FU) has exhibited effectiveness against cancer, novel therapeutic strategies are needed to enhance its antitumor efficiency and modulate its cytotoxity. Apigenin, a flavonoid present in fruits and vegetables, is a potent dietary phytochemical effective in cancer chemoprevention. AIM: This study was undertaken to investigate the potential synergistic antitumor activity of apigenin and 5-FU on Solid Ehrlich carcinoma (SEC). METHODS: Eighty Swiss albino male mice were divided into four equal groups: vehicle treated control SEC, SEC+5-FU, SEC+apigenin, SEC+ 5-FU+apigenin...
December 23, 2016: Toxicology and Applied Pharmacology
https://www.readbyqxmd.com/read/28024292/adjuvant-effect-of-asparagus-racemosus-willd-derived-saponins-in-antibody-production-allergic-response-and-pro-inflammatory-cytokine-modulation
#9
Nimisha Tiwari, Vivek Kumar Gupta, Pallavi Pandey, Dinesh Kumar Patel, Suchitra Banerjee, Mahendra Pandurang Darokar, Anirban Pal
The study manifests the immunoadjuvant potential of saponin rich fraction from Asparagus racemosus in terms of cellular and humoral immune response that can be exploited against microbial infections. Asparagus racemosus (AR) has been attributed as an adaptogen and rasayana in traditional medication systems for enhancing the host defence mechanism. Spectrophotometric and HPTLC analysis ensured the presence of saponins. The saponin rich fractions were tested for immunoadjuvant property in ovalbumin immunised mice for the humoral response, quantified in terms of prolonged antibody production upto a duration of 56days...
February 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/27942841/membrane-related-hallmarks-of-kinetin-induced-pcd-of-root-cortex-cells
#10
Andrzej Kaźmierczak, Magdalena Doniak, Przemysław Bernat
Changes in cellular membrane potential and their fluidisation are the hallmarks of cell death induction with kinetin in root cortex. Programmed cell death (PCD), one of the essential processes in plant development, is still poorly understood. In this paper, the scientific plant model, V. faba ssp. minor seedling roots after kinetin application which triggers off programmed death of cortex cells, was used to recognise membrane-related aspects of plant cell death. Spectrophotometric, reflectometric and microscopic studies showed that the PCD induced by kinetin is accompanied by higher potassium ions leakage from roots, loss of plasma and ER membrane potentials (expressed by their lower amounts and higher index of fatty acid unsaturation), malformation of nuclear envelope, lower total lipid amount and formation of their peroxides, lower amount of phospholipids and changes in their composition...
December 10, 2016: Plant Cell Reports
https://www.readbyqxmd.com/read/27930713/detecting-methemoglobinemia-in-animals-with-a-drop-of-blood
#11
Toni G Patton, Stephen L Blamer, Katherine E Horak
A major concern during pesticide development and use is the impact on non-target species, such as raptors or domestic cats and dogs. Sodium nitrite and para-aminopropiophenone (PAPP) are two toxicants currently being studied for the control of invasive species, such as starlings and feral swine. When given to an animal these compounds oxidize hemoglobin, which renders it unable to carry oxygen resulting in methemoglobinemia. This study developed a method to estimate methemoglobin levels in mammals and birds by examining the efficacy of sodium nitrite to induce the conversion of hemoglobin to methemoglobin...
2016: PloS One
https://www.readbyqxmd.com/read/27899761/rehabilitation-augments-hematoma-clearance-and-attenuates-oxidative-injury-and-ion-dyshomeostasis-after-brain-hemorrhage
#12
Michael R Williamson, Kristen Dietrich, Mark J Hackett, Sally Caine, Colby A Nadeau, Jasmine R Aziz, Helen Nichol, Phyllis G Paterson, Frederick Colbourne
BACKGROUND AND PURPOSE: We assessed the elemental and biochemical effects of rehabilitation after intracerebral hemorrhage, with emphasis on iron-mediated oxidative stress, using a novel multimodal biospectroscopic imaging approach. METHODS: Collagenase-induced striatal hemorrhage was produced in rats that were randomized to enriched rehabilitation or control intervention starting on day 7. Animals were euthanized on day 14 or 21, a period of ongoing cell death...
January 2017: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/27890701/evaluation-for-substitution-of-stem-bark-with-small-branches-of-myrica-esculenta-for-medicinal-use-a-comparative-phytochemical-study
#13
Bhavana Srivastava, Vikas C Sharma, Pramila Pant, N K Pandey, A D Jadhav
BACKGROUND: Over exploitation of many traditional medicinal plants like Myrica esculenta has become a threat and in the near future, many medicinal plants may be unavailable for use of industry. OBJECTIVE: Present study outlines the concept of plant part substitution. Stem bark and small branches of M. esculenta are compared on the basis of physicochemical analysis, phytochemical analysis, total phenolic contents, total flavonoid contents and high performance thin layer chromatography (HPTLC) to evaluate the possibilities of using small branches in place of stem bark...
October 2016: Journal of Ayurveda and Integrative Medicine
https://www.readbyqxmd.com/read/27867571/role-of-oxidative-stress-and-outcome-of-various-surgical-approaches-among-patients-with-bullous-lung-disease-candidate-for-surgical-interference
#14
Ahmed Farouk, Mohammed H Hassan, Mohammed Alaa Nady, Mohammed Farouk Abdel Hafez
BACKGROUND: Bullous lung disease is characterized by formation of blebs, bullae and emphysema. We investigate the role of oxidative stress in the pathogenesis of bullous lung disease and compare between conventional thoracotomy versus video assisted thoracoscopic approach in surgical management of such patients. METHODS: This study was a prospective case control study and it was carried out on 21 patients (16 males and 5 females) with bullous lung disease selected as candidate for surgical interference...
October 2016: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/27855914/spectrophotometric-determination-of-synthetic-colorants-using-pso-ga-ann
#15
Ali Benvidi, Saleheh Abbasi, Sajjad Gharaghani, Marzieh Dehghan Tezerjani, Saeed Masoum
Four common food colorants, containing tartrazine, sunset yellow, ponceau 4R and methyl orange, are simultaneously quantified without prior chemical separation. In this study, an effective artificial neural network (ANN) method is designed for modeling multicomponent absorbance data with the presence of shifts or changes of peak shapes in spectroscopic analysis. Gradient descent methods such as Levenberg-Marquardt function are usually used to determine the parameters of ANN. However, these methods may provide inappropriate parameters...
April 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27802175/neurotransmitter-alteration-in-a-testosterone-propionate-induced-polycystic-ovarian-syndrome-rat-model
#16
Nirja K Chaudhari, Laxmipriya P Nampoothiri
BACKGROUND: Polycystic ovarian syndrome (PCOS), one of the leading causes of infertility seen in women, is characterized by anovulation and hyperandrogenism, resulting in ovarian dysfunction. In addition, associations of several metabolic complications like insulin resistance, obesity, dyslipidemia and psychological co-morbidities are well known in PCOS. One of the major factors influencing mood and the emotional state of mind is neurotransmitters. Also, these neurotransmitters are very crucial for GnRH release...
October 29, 2016: Hormone Molecular Biology and Clinical Investigation
https://www.readbyqxmd.com/read/27797222/histological-subtype-of-ovarian-cancer-as-a-determinant-of-sensitivity-to-formamidine-derivatives-of-doxorubicin-in-vitro-comparative-studies-with-skov-3-and-es-2-cancer-cell-lines
#17
COMPARATIVE STUDY
M Denel-Bobrowska, M Lukawska, I Oszczapowicz, A Marczak
BACKGROUND: Development of new apoptosis-inducing drugs is a promising trend in anticancer therapy. For this purpose several formamidinoderivatives of doxorubicin were synthesized. The aim of our study was to investigate effects of the five formamidinodoxorubicins in the ES-2 human ovarian clear cell carcinoma line, for comparison with data obtained previously for SKOV-3 human ovarian adenocarcinoma cells, to answer the question of whether and to what extent the histological cell type is a possible determinant of sensitivity to tested anthracyclines...
2016: Asian Pacific Journal of Cancer Prevention: APJCP
https://www.readbyqxmd.com/read/27794621/insights-into-the-thermodynamics-of-polymer-nanodot-human-serum-albumin-association-a-spectroscopic-and-calorimetric-approach
#18
Arpan Bhattacharya, Somnath Das, Tushar Kanti Mukherjee
With the advent of newer luminescent nanoparticles for bioimaging applications, their complex interactions with individual biomolecules need to be understood in great detail, before their direct application into cellular environments. Here, we have presented a systematic and detailed study on the interaction between luminescent polymer nanodots (PNDs) and human serum albumin (HSA) in its free and ligand-bound state with the help of spectrophotometric and calorimetric techniques. At physiological pH (pH = 7...
November 22, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/27793736/spectrophotometric-reading-of-eucast-antifungal-susceptibility-testing-of-aspergillus-fumigatus
#19
J Meletiadis, K Leth Mortensen, P E Verweij, J W Mouton, M C Arendrup
OBJECTIVES: Given the increasing number of antifungal drugs and the emergence of resistant Aspergillus isolates, objective, automated and high-throughput antifungal susceptibility testing is important. The EUCAST E.Def 9.3 reference method for MIC determination of Aspergillus species relies on visual reading. Spectrophotometric reading was not adopted because of concern that non-uniform filamentous growth might lead to unreliable and non-reproducible results. We therefore evaluated spectrophotometric reading for the determination of MICs of antifungal azoles against Aspergillus fumigatus...
February 2017: Clinical Microbiology and Infection
https://www.readbyqxmd.com/read/27777928/cervicovaginal-fluid-acetate-a-metabolite-marker-of-preterm-birth-in-symptomatic-pregnant-women
#20
Emmanuel Amabebe, Steven Reynolds, Victoria Stern, Graham Stafford, Martyn Paley, Dilly O C Anumba
Changes in vaginal microbiota that is associated with preterm birth (PTB) leave specific metabolite fingerprints that can be detected in the cervicovaginal fluid (CVF) using metabolomics techniques. In this study, we characterize and validate the CVF metabolite profile of pregnant women presenting with symptoms of threatened preterm labor (PTL) by both (1)H-nuclear magnetic resonance spectroscopy (NMR) and enzyme-based spectrophotometry. We also determine their predictive capacity for PTB, singly, and in combination, with current clinical screening tools - cervicovaginal fetal fibronectin (FFN) and ultrasound cervical length (CL)...
2016: Frontiers in Medicine
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