35 results on '"Chemical inhibitors"'
Search Results
2. NUEVAS DIANAS MOLECULARES EN CÁNCER DE GINECOLÓGICO.
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Elena Leiva-Suero, Lizette, Fabián Salazar-Garcés, Luis, de las Mercedes Quishpe-Jara, Graciela, Fernández, Gerardo, Villacís Valencia, Sandra Elizabetn, and Chicaiza Tayupanta, Jesús Onorato
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THERAPEUTIC use of antineoplastic agents ,RESEARCH ,INFERENTIAL statistics ,DISEASE progression ,IMMUNOMODULATORS ,APOPTOSIS ,CANCER patients ,CELLULAR signal transduction ,MOLECULAR biology ,GENETIC markers ,PAPILLOMAVIRUS diseases ,DESCRIPTIVE statistics ,CERVIX uteri tumors ,TUMOR markers ,MEMBRANE proteins ,LONGITUDINAL method ,CARRIER proteins ,IMMUNOTHERAPY ,CHEMICAL inhibitors - Abstract
Copyright of Enfermería Investiga: Investigaciin, Vinculación, Docencia y Gestiin is the property of Revista Enfermeria Investiga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
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3. Predicción de la afinidad de ligandos antagonistas por receptores de adenosina A2A usando árboles de decisión.
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Huici Corrales, Adonis, Morales Helguera, Aliuska, Ancede Gallardo, Evys, Molina Ruiz, Reinaldo, Teijeira Bautista, Marta, Abreu Stincer, Guillermo, and Martínez Albelo, Eugenio
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DECISION trees , *ADENOSINES , *NEURODEGENERATION , *CHEMICAL inhibitors , *CLUSTER analysis (Statistics) - Abstract
Neurodegenerative diseases are being treated by modulating adenosine receptors with more effective, safe and selective antagonists. The objective of the study was to develop a methodology to obtain classification models based on decision tree algorithms and descriptors from 0D to 2D of non-congenital families of organic compounds to qualitatively predict lig-and-RAA2A affinity. For this purpose, a non-congeneric database of 315 antagonists was constructed and cured with its inhibition constant in nano molar, labeled as potent and weak. The Dragon and ISIDA / QSPR programs were used to calculate molecular descriptors and five groups of descriptors were obtained. In each group 50 descriptors were selected using the mRMR criterion. The database was divided into Training, Test and External series through a random selection and a generalized k-means cluster analysis. Classifiers were developed and validated using the WEKA program. The results were analyzed using the statistical tests of Friedman and Wilcoxon. The significant influence of parameter m of algorithm J48 on the predictivity was verified for the models that used the descriptors of the aug.a-b and hyb.aug.a groups of ISIDA / QSPR. The best performance model was obtained from the selected descriptors of the ISIDA-all group with a value of m = 6 and reached 90.6% prediction on the External series. The methodology developed to obtain classification models based on decision tree algorithms and descriptors from 0D to 2D of non-congenital families of organic compounds is effective in qualitatively predicting ligand- RAA2A affinity with accuracy, specificity and selectivity greater than 90 %. [ABSTRACT FROM AUTHOR]
- Published
- 2019
4. Efecto inhibitorio de fracciones peptídicas derivadas de la hidrólisis de semillas de chía (Salvia hispanica) sobre las enzimas α-amilasa y α-glucosidasa.
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Sosa Crespo, Irving, Laviada Molina, Hugo, Chel-Guerrero, Luis, Ortiz-Andrade, Rolffy, and Betancur-Ancona, David
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CHIA , *HYDROLYSIS , *ALPHA-amylase , *ALPHA-glucosidases , *PEPTIDES , *AMINO acids , *DIABETES , *AMYLASES , *PLANT proteins , *GLYCOSIDASES , *PLANT extracts , *ENZYME inhibitors , *PHARMACODYNAMICS , *CHEMICAL inhibitors - Abstract
Introduction: biopeptides are amino acid sequences with biological functions about metabolism and carbohydrates absorption.Objective: the aim of this study was the evaluation of the inhibitory effect of peptide fractions derivatives of the hydrolysis of Salvia hispanica against α-amylase and α-glucosidase enzymes to know their activity on the carbohydrates metabolism.Material and Methods: the fraction rich in protein was hydrolyzed by two enzymatic systems: Alcalase®-Flavourzyme® and pepsin-pancreatine. The grade of hydrolysis was determined for the samples. The hydrolyzed samples were centrifuged and the soluble portion was ultra-filtered using different cut membranes. The content of protein was determined for each fraction. An in vitro analysis was made, measuring the percentage of inhibition of the Salvia hispanica fractions against α-amylase and α-glucosidase.Results: the enzymatic system showing the highest grade of hydrolysis (63.53%) was pepsin-pancreatine. From the ultrafiltration, five peptide fractions were obtained: 10 kDa, 5-10 kDa, 3-5 kDa, 1-3 kDa and 1 kDa. The highest protein content was for these fractions: 10 kDa and 5-10 kDa, (0.90 and 0.93 mg/ml, respectively) for pepsin-pancreatine. The inhibition percentages obtained were 85.61% and 79.19% for the 10 kDa and 5-10 kDa fractions, respectively, for the α-amylase enzyme. With respect to the α-glucosidase enzyme, the highest inhibition was for the 10 kDa fraction, with 96.91%.Conclusion: the peptide fractions obtained from the chia may increase the natural sources for the preparation of functional foods important for the diabetic patient's diet. [ABSTRACT FROM AUTHOR]- Published
- 2018
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5. EFECTO IN VIVO DEL VINO TINTO SIN DILUIR, DILUIDO (75%) Y SIN ALCOHOL SOBRE EL DAÑO GENOTÓXICO INDUCIDO POR METALES PESADOS CON POTENCIAL CANCERÍGENO: CROMO [VI].
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García Rodríguez, María del Carmen, Nava, Rodrigo Aníbal Mateos, Altamirano Lozano, Mario, and Mateos Nava, Rodrigo Aníbal
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ANIMAL experimentation , *CARCINOGENS , *CHROMIUM compounds , *DNA , *MUTAGENS , *PREVENTIVE health services , *RATS , *WINES , *OXIDATIVE stress , *CHEMICAL inhibitors - Abstract
Introduction: the carcinogenesis may be initiated and promoted by the oxidative DNA damage. The compounds of chrome (Cr [VI]) cause oxidative stress (EOx) and are recognized as carcinogens in humans. In this sense, it is proposed that drinks with a high antioxidative potential, such as red wine, may have protective or modulatory effects on the oxidative DNA damage.Objective: to study the effects of the administration in vivo of undiluted, diluted (75%) and alcohol-free red wine on the genotoxic damage induced by carcinogenic metals (Cr [VI]), by evaluating the micronucleus (MN) in polychromatic erythrocytes (EPC) in mice (CD-1).Material and Method: it was randomly organized the follow groups: (i) control, (ii) undiluted, diluted and alcohol-free red wine (free access), (iii) CrO3 (20 mg/kg by intraperitoneal route) and (iv) CrO3-red wine. The evaluations were made in blood samples obtained from the caudal vein, in which it was identified the MN and EPC before, during and after treatments.Results and Discussion: the red wine (diluted and alcohol-free) was capable of decreasing the averages of MN induced by CrO3, demonstrating its modular capacity in vivo in the oxidative DNA damage caused by EOx-induced carcinogens. The administration of only undiluted red wine presented toxic effects.Conclusions: our results raises expectations on the use of substances like the red wine for the protection or modulation of genotoxic damage, encouraging its application in the carcinogenic and mutagenic processes. [ABSTRACT FROM AUTHOR]- Published
- 2015
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6. Angioedema hereditario: causa rara de dolor abdominal.
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Salas-Lozano, Nereo Guillermo, Meza-Cardona, Javier, González-Fernández, Coty, Pineda-Figueroa, Laura, and de Ariño-Suárez, Mauricio
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GENETIC disorders ,CHEMICAL inhibitors ,VOMITING - Abstract
Copyright of Cirugía y Cirujanos is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
7. Uso de extractos de plantas como inhibidores de corrosión.
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Tejeda Benítez, Lesly Patricia, Meza Castellar, Pedro Javier, Altamiranda Percy, Edgar David, and Berrocal Bravo, María José
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CORROSION & anti-corrosives , *CORROSION prevention , *BIODEGRADABLE materials , *PLANT extracts , *CHEMICAL inhibitors , *DETERIORATION of materials - Abstract
Corrosion problems are common in the chemical, petroleum, naval, civil construction industry, in transportation, communication systems, among others. Corrosion inhibitors are widely used in the control and prevention of this phenomenon; most of the compounds used for this purpose are often too toxic, expensive and harmful to the environment and humans. This has created the need for corrosion inhibitors that are environmentally friendly and inexpensive. The plant extracts are biodegradable and represent a renewable source of chemical compounds that have a high potential as inhibitors. This paper presents a review of the variety of higher plants and algae that have been used as corrosion inhibitors showing the type of metal (steel, zinc and aluminum) and environmental exposure conditions (acidic and neutral). [ABSTRACT FROM AUTHOR]
- Published
- 2014
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8. Divergencias entre guías de 2013 y 2014 de la hipertensión arterial. Posición de la Sociedad Centroamericana y del Caribe de Hipertensión y Prevención Cardiovascular1.
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Morales-Salinas, Alberto, Wyss, Fernando, Coca, Antonio, Ramírez, Agustín J., Valdez, Osiris, and Valerio, Luis F.
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CARDIOVASCULAR disease prevention , *HYPERTENSION risk factors , *THERAPEUTICS , *BETA adrenoceptors , *HYPERTENSION , *MEDICAL protocols , *CHEMICAL inhibitors - Abstract
Between the end of 2013 and the beginning of 2014 the most internationally influential hypertension guidelines were published. Although there are no major differences between them, there are discrepancies that can have an impact on treatment and prognosis for individuals with hypertension. This article analyzes the main controversial elements in the guides and presents the recommendations of the Sociedad Centroamericana y del Caribe de Hipertensión y Prevención Cardiovascular (Caribbean Society for Hypertension and Cardiovascular Prevention). The main differences are found a) in the categorization of prehypertension, b) in the use of global cardiovascular risk in the decision to begin antihypertensive treatment, c) in the validity of beta-blockers as first-line drugs in treating uncomplicated hypertension, and d) the increase in the therapeutic goal of maintaining values between ≤ 140/90 and ≤ 150/90 mmHg in patients over 60 years of age with no history of diabetes or chronic kidney disease. All the factors in favor of and against accepting each of these four controversial criteria are analyzed critically and the observations made by the Society are included. The conclusion is that there are pros and cons for all controversial elements in the hypertension guides. However, the weight of the evidence and clinical judgment favor subdividing prehypertension into stages I and II, seeking a therapeutic goal of maintaining systolic blood pressure below 140 mmHg in all the hypertensive patients under 80 years of age, retaining beta-blockers as first-line drugs in uncomplicated hypertension, and not delaying the start of drug treatment for hypertension stage I with low global cardiovascular risk. Finally, seven recommendations by the Society based on the analysis are included. [ABSTRACT FROM AUTHOR]
- Published
- 2015
9. ESTUDIO DE LOS CAMBIOS DE LA ACTIVIDAD ANTIOXIDANTE EN BEBIDAS DE CAFÉ DURANTE SU PERIODO DE VIDA ÚTIL USANDO MÉTODOS IN-VITRO Y EX-VIVO.
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Julián LONDOÑO, L., Mauricio NARANJO, C., and Mónica M. QUINTERO, O.
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ANTIOXIDANTS , *CHEMICAL inhibitors , *LOW density lipoproteins , *POLYPHENOLS , *COFFEE - Abstract
Background: Antioxidants have been one of the commercial concepts with highest impact in functional food market; however, their statement turns out a controversial topic among regulatory agencies worldwide, due to the complexity involved in demonstrating the presence and bioactivity of these antioxidants in the food. In this context, recent researches have attributed antioxidant properties to coffee beverages. Objectives: The aim of this work was to determine by in-vitro methods that coffee beverages contain phenolic substances, which may act as antioxidants, as well as evaluate how this activity can vary over time. Methods: 48 Coffee products were evaluated at two storage time conditions, namely, at the beginning and the end of their shelf life, determining the total phenolic content and their antioxidant activity by ABTS (radical capture of 2, 2 '-azino-bis-(3-ethyl benzotiazolin -6 - ammonium sulfonate) and DPPH (Capture the radical 2,2-diphenyl-l-picrilhidracilo); FRAP was also determined to know the ferric iron reducing activity The objective of the above was to establish the content of phenolic antioxidant to be declared on the label. Results: The content of antioxidant polyphenols was different depending on the coffee type; the content was 328.61 ± 31.35 and 297.17 ± 68.48 mg gallic acid equivalents per 100 mL of beverage in roasted and soluble coffees respectively. The results obtained by the methods of ABTS, DPPH and FRAP showed through a principal components analysis that they are correlated with each other and that the storage time has an effect on the antioxidant activity of the products. Additionally, the ex-vivo antioxidant capacity was evaluated on two samples, roasted and soluble coffee beverages by the lipid peroxidation assay of the Low Density Lipoprotein (LDL); it was found that coffee beverages prevent the LDL oxidation, according to the results of polyphenols contents. Conclusions: The results allowed establishing the specifications of the content of antioxidants in coffee products to be declared on the label. This study shows that with these analysis methods the bioactivity of coffee products and its stability over time can be demonstrated. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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10. Terapia biológica en enfermedades reumatológicas.
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Usarte-Gil, Manuel F., Acevedo-Vásquez, Eduardo M., and Alarcón, Graciela S.
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THERAPEUTIC use of monoclonal antibodies , *DRUG therapy for rheumatism , *ANKYLOSING spondylitis , *ANTIRHEUMATIC agents , *BIOTHERAPY , *MONOCLONAL antibodies , *OSTEOPOROSIS , *PATIENT safety , *RECOMBINANT DNA , *RHEUMATISM , *RHEUMATOID arthritis , *SYSTEMIC lupus erythematosus , *TUMOR necrosis factors , *CHEMICAL inhibitors , *PHARMACODYNAMICS - Abstract
The advent of biologic therapies in Rheumatology has modified significantly the prognosis of patients with rheumatoid arthritis (RA), juvenile arthritis (JA), ankylosing spondylitis (AS), among others. In contrast to the conventional therapies, these biological therapies are directed at specific targets being those a cell line, an inflammatory mediator, or a surface receptor. These compounds are produced by live cells using recombinant DNA technology. They can have human and animal components [chimerics (Xi), humanized (Zu)] or be completely human (H); this is recognized by the letters included in their names. The first compound used in Rheumatology was etanercept (anti- tumor necrosis factor) which was approved by the FDA in 1998; however other anti-TNF compounds have proven to be beneficial in RA as well as in AS and JA. The interleukin-1 (IL-1) inhibitors are rarely used in RA at the present time, but IL-6 inhibitors and agents directed against CTLA-4 (Cytotoxic T lymphocyte antigen) are. There is also a compound against BLyS (B-lymphocyte stimulator) which is used in systemic lupus erythematosus and other directed at RANKL (receptor activator of nuclear factor-κB ligand) which is used in osteoporosis. With the advances made in the understanding of the pathogenesis of the rheumatic diseases, new therapeutic targets are being recognized. In the years to come this field will expand in geometric proportions. [ABSTRACT FROM AUTHOR]
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- 2013
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11. REMOCIÓN FOTOCATALÍTICA DE CIANURO EMPLEANDO CATALIZADORES TiO2, FeMoO4/TiO2, HPMoCu/TiO2 CON RADIACIÓN SOLAR SIMULADA Y REACTOR COLECTOR CILÍNDRICO PARABÓLICO.
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Barbosa, Aida L. and Castro, Isel
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CHEMICAL inhibitors ,SOLUTION mining ,TITANIUM dioxide ,ORE-dressing ,IN situ processing (Mining) - Abstract
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- Published
- 2012
12. La abstinencia al GABA: 20 años de un modelo de hiperexcitabilidad neuronal.
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Calixto, Eduardo
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GABA , *NEUROTRANSMITTERS , *NEUROLOGICAL research , *NEUROTRANSMITTER receptors , *CHEMICAL inhibitors , *DRUG withdrawal symptoms - Abstract
The sudden interruption of increase in the concentration of the synaptic cleft of the inhibitory neurotransmitter in the cerebral cortex, the γ-amino butyric acid (GABA), determines an increase in the neuronal activity. GABA withdrawal is a heuristic analogy with withdrawal symptoms developed by other GABA receptor-agonists such as benzodiazepines, barbiturates, neurosteroids and alcohol. GABA withdrawal is a model of neuronal hyperexcitability in complete animal validated by EEG, in which complex spikes-wide of high-frequency and amplitude appear. In brain slices, GABA withdrawal was identified by increased firing synchronization of pyramidal neurons and by changes in the active properties of the neuronal membrane. The increase in neuronal excitability of this model is the result of dynamic changes in consecutive pre- and post-synaptic components such as: a) the decrease in the synthesis/release of GABA; b) the decrease in the expression and composition of GABAA receptors associated with increased calcium entry into the cell. This model is an excellent bioassay to study partial epilepsy, epilepsy refractory to drug treatment and a model to reverse or prevent the generation of abstinence from different drugs. [ABSTRACT FROM AUTHOR]
- Published
- 2012
13. Modelaje Molecular de E-1-[4'-(3-(sustituido) acriloil) fenil]-3-tosilureas.
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León, Caritza, Colman, Trina, and Domínguez, José
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MOLECULAR models ,PHENYL compounds ,ANTIMALARIALS ,CHEMICAL inhibitors ,PLASMODIUM falciparum ,DRUG resistance ,CHLOROQUINE - Abstract
Copyright of Revista de Investigación is the property of Universidad Pedagogica Experimental Libertador and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2012
14. Efecto del Almacenamiento a Diferentes Temperaturas sobre la Calidad de Tuna Roja (Opuntia ficus indica (L.) Miller).
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Ochoa, Carlos E. and Guerrero, José A.
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PEARS , *OPUNTIA , *SHELF-life dating of food , *ANTIOXIDANTS , *CHEMICAL inhibitors - Abstract
The effect of the storage at different temperatures on the quality of red prickle pear (Opuntia ficus indica (L.) Miller) San Martín variety. The fruit was stored at 4±1, 9±2, and 28±2°C for determining its shelf life. Once a week, physicochemical, enzymatic, antioxidant and microbiological characteristics were evaluated until fruit showed no edible characteristics. Time and storage temperature were the two parameters that significantly affected (p<0.05) weight loss, texture and activity of polyphenoloxidase in pear peel. Phenolic compounds, antioxidant capacity, and pectinesterase activity did not show significant difference (p>0.05) during storage time. However, antioxidant capacity presented a significant increase with time. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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15. EVALUACIÓN DEL COLOR DURANTE EL ALMACENAMIENTO DE LA PULPA DE BANANO VERDE IMPREGNADA AL VACÍO CON SOLUCIONES ANTIPARDEANTES.
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Cortés R., Misael, Pinto A., Lina M., and Giraldo G., Germán A.
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FRUIT storage , *BANANAS , *ANTIOXIDANTS , *SULFITE pulping process , *OXIDASES , *ROOT cellars , *CHEMICAL inhibitors - Abstract
Vacuum impregnation is a technique applied by matrix engineering as the mechanism to incorporate the solutions to the interior of an alimentary matrix. The development of the color of the pulp of unripe Banana (PUB) (Musa cavendish) was evaluated in different storage conditions: Time 0, 3, 6, 9, 12, and 15 days, Temperature 4, 20, and 30°C, packed with vacuum (WV) and without vacuum (NV) under sulfite treatment (500, 1000, 1500 mg/kg PUB) and the antioxidant interaction (60, 90, 120 mg/100 g PUB) , acidulant (50, 150, 250 mg/100 g PUB) using the vacuum impregnation (VI) technique. The parameters of color were evaluated using CIEL *a *b *, in terms of lighting (L*) and chromaticity a* and b*. The ANOVA test showed significant statistical differences (P < 0,05) in all the parameters related to the times of storage, temperature, packing conditions, areas of the pulp, and concentration of the solutions. In all of the cases the core part of the pulp was darker than the external part. The storage of the Banana pulp at 4°C, packed under vacuum, allowed to get acceptable commercial characteristics of color during the 15 days of storage. The treatment with metabisulfites at 500 mg/kg PUB and the combination of Ascorbic (90 mg/100 g PUB) and Citric (50 mg/100 g PUB) acids, gave the best characteristics of color in time at the different temperatures and concentrations. [ABSTRACT FROM AUTHOR]
- Published
- 2011
16. Actividad Inhibitoria del Extracto de Heliopsis longipes Sobre Fusarium oxysporum f. sp lycopersici.
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González Morales, Susana, Flores López, María Liliana, Benavides Mendoza, Adalberto, and Flores Olivas, Alberto
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FUSARIUM oxysporum , *TOMATO diseases & pests , *FUSARIUM diseases of plants , *PHYTOPATHOGENIC microorganisms , *CHEMICAL inhibitors , *HELIOPSIS - Abstract
A total of 17 Fusarium sp. isolates were obtained from tomato roots with wilt symptoms. Nine isolates were identified as Fusarium oxysporum f. sp. lycopersici; isolates pathogenicity was determined. More severe symptoms were caused by one of the isolates named FOL10. Such isolate was selected to have the Heliopsis longipes ethanol extract minimum inhibitory dose evaluated in vitro. The affinin concentration was determined as the extract main component. The estimated median lethal dose was 164.2 µg -1mL of affinin, and the lethal dose 90 was 348.6 µg mL-1 of affinin. [ABSTRACT FROM AUTHOR]
- Published
- 2011
17. EVALIACIÓN DE LA ACTIVIDAD ANTIOXIDANTE "In vivo" DE TRES FRUTOS DE LA AMAZONÍA: Gustavia augusta L., Grias neuberthii Macbr y Theobroma bicolor.
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Garcia, Dora, Sotero, Victor, Mancini, Dalva, Pavan Torres, Rosângela, and Mancini Filho, Jorge
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ANTIOXIDANTS ,CHEMICAL inhibitors ,FRUIT ,UNSATURATED fatty acids ,THEOBROMA ,PATASHTE - Abstract
Copyright of Revista de la Sociedad Química del Perú is the property of Sociedad Quimica del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2011
18. Hidrogenación de Metil Oleato con Catalizadores de Ru-Sn/Al2O3: Método Sol-gel vs. Impregnación.
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Echeverri, David A., Rios, Luis A., and Marin, Juan M.
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HYDROGENATION , *CHEMICAL inhibitors , *CATALYSIS , *CATALYSTS , *FATTY alcohols , *UNSATURATED fatty acids - Abstract
In this work, the effect of the preparation method (sol-gel vs. impregnation) over conversion and selectivity to oleyl alcohol in the hydrogenation of methyl oleate over Ru-Sn/Al2O3 catalysts at 270°C and 5 MPa was evaluated. The catalysts were characterized by SEM-EDS, TPR, XRD and surface area by nitrogen adsorption. The sol-gel method produced high dispersion of metals in the support, however catalysts prepared by sol-gel method were less reducible. For both methods an optimum Sn/Ru atomic ratio that allowed higher percentage of unsaturated alcohol was found. For the impregnation method this atomic ratio was 2 and for sol-gel method was 1. However, higher conversions and higher selectivity toward the oleyl alcohol were obtained with the impregnation method, using the optimum atomic ratio. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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19. PROPIEDADES ANTIOXIDANTES DE LA GUAYABA (Psidium guajava L.).
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Palomino Pacheco, Miriam, Guija Poma, Emilio, and Lozano Reyes, Nancy
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GUAVA ,ANTIOXIDANTS ,FREE radicals ,HYDROXYL group ,THIOUREA ,CHEMICAL inhibitors - Abstract
Copyright of Revista de la Sociedad Química del Perú is the property of Sociedad Quimica del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2009
20. Evaluación del Poder Antioxidante de Fracciones de Aceite Esencial Crudo de Schinus molle L. obtenidas por Destilación al Vacío.
- Author
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Guala, María S., Elder, Heriberto V., Perez, Gustavo, and Chiesa, Alejandro
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ANTIOXIDANTS , *CHEMICAL inhibitors , *ESSENTIAL oils , *DISTILLATION , *GAS chromatography - Abstract
The antioxidant characteristics of the Schinus molle L (molle, aguaribay) raw essential oil we reevaluated and compared with different cuts from the same oil obtained by vacuum distillation. The samples were analysed using GS/MS chromatography and the antioxidant efficiency was determined using the DPPH method, 2.2 Diphenyl 1 picrylhydrazyl. An analysis of the results we may conclude that the fraction is the heaviest it has greater power anti radical. The results show that the heaviest fraction contains higher concentration of Terpinen-4-ol and Germacreno D, compounds that are collectors of free radicals. Therefore, the heaviest fraction has greater antiradical power. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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21. Cannabis, neuronas inhibidoras y evolución progresiva de la esquizofrenia.
- Author
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FREEDMAN, ROBERT
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SCHIZOPHRENIA , *NEOCORTEX , *PSYCHIATRY , *CANNABIS (Genus) , *NEUROBIOLOGY , *CHEMICAL inhibitors ,EDITORIALS - Abstract
El artículo se centra en el algunos artículos publicados en el presente número de la revista "American Journal of Psychiatry" sobre el deterioro de la función inhibidora de las interneuronas de la neocorteza en la esquizofrenia y el efecto del consumo de Cannabis y la esquizofrenia en la pérdida de tejido cerebral.
- Published
- 2008
22. Evaluación de la capacidad antioxidante de siete plantas medicinales peruanas.
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Castañeda, C. B., Ramos, LL. E., and Ibáñez, V. L.
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PLANT extracts , *MEDICINAL plants , *VITAMIN C , *ANTIOXIDANTS , *CHEMICAL inhibitors , *CINNAMON tree - Abstract
We evaluated the antioxidant activity of twentynine extracts of the following medicinal plants: Cinnamomum zeylanicum "canela", Calophyllum brasiliense "lagarto caspi", Myrciaria dubia "camu camu", Minthostachys mollis "muña", Alchornea castaneifolia "hiporuro", Smallanthus sonchifolius "yacón", Lepidium peruvianum and Lepidium meyenii "maca", by the bleaching method of 2,2-diphenyl-1-picrylhidrazyl (DPPH) radical. The antioxidant capacity obtained at the concentrations of 1 ug/mL, 50 ug/mL, 100 ug/mL and 200 ug/mL were: canela (ethanolic extract from bark) 97,59% at 1 ug/mL concentration, lagarto caspi (methanolic extract from leaves) 99,76% at 50 ug/mL, camu camu (methanolic extract from the fruit) 98,09% at 50 ug/mL, muña (watery extract from leaves) 92,41% at 50 ug/mL, hiporuro (methanolic extract from leaves) 100,57% at 100 ug/mL, Lagarto caspi (watery extract from leaves) 110,56% at 100 ug/mL, Lepidium peruvianum (watery extract from hypocotyl) 95,55% at 200 ug/mL and Lepidium meyenii (methanolic extract from hipocotyl) 88,21% at 200 ug/mL, in comparison with ascorbic acid (Vitamin C) that presented an antioxidant activity of 92,82%. [ABSTRACT FROM AUTHOR]
- Published
- 2008
23. Potencial Antioxidante de Bauhinia Kalbreyeri Harms (FABACEAE).
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Murillo, Elizabeth, Lombo, Oscar, Tique, Margarita, and Méndez, Jonh J.
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BAUHINIA , *ANTIOXIDANTS , *FREE radicals , *PLANT extracts , *CHEMICAL inhibitors - Abstract
The article examines the antioxidant activity potential of Bauhinia Kalbreyeri Harms. The authors explain that the plant has been determined by the Colombian ethnomedicine as antidiabetic. They evaluate the extracts for free radicals by DPPH method. Ethanol mixed on the extracts showed the higher DPPH radical scavenging activity than 90% in almost all the concentration tested.
- Published
- 2007
- Full Text
- View/download PDF
24. ESTUDIO DE INHIBIDORES ECOLÓGICOS Y NATURALES.
- Author
-
Armaignac, Elaine Ojeda and Cortón, Romelia Hing
- Subjects
- *
CHEMICAL inhibitors , *ALCOHOLIC beverages , *PRECIPITATION (Chemistry) , *ELECTROCOAGULATION (Chemistry) , *CORROSION & anti-corrosives - Abstract
The search of inhibitors obtained from residuum products is a theme of primordial importance, we dispose of a residual that is the waste liquor (mosto) of the etilic alcohol production, from which must be extracted economic and efficiently the inhibitor compounds of the corrosion. The objectives of the work are To determine the inhibitor properties of the solid compounds obtained from the mosto by alcoholic precipitation and by electrocogulation, so as the efficiency of these compounds at different pH values with carbon steel. It was comprobated that these solid compounds obtained starting from the mosto are adsortion inhibitorrs being those obtained by electrocoagulation more efficient than the obtained by alcoholic precipitation. Carbon steel was evaluated like stable at pH values of 6 and 9 in the table of stability criteria, using this inhibitor. It was utilized the potentiostatic method to determine the corrosion rate values. [ABSTRACT FROM AUTHOR]
- Published
- 2006
25. ESTANDARIZACIÓN DE LA MEDICIÓN TURBIDIMÉTRICA PARA LA DETERMINACIÓN DE INHIBIDORES EN LECHE POR EL SISTEMA DIRAMIC.
- Author
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Lamazares, J. Alvarez, Armenteros, Mabelin, Ponce, P., and Quiñones, Celia
- Subjects
- *
RAW milk , *COMPOSITION of milk , *BACILLUS (Bacteria) , *MILK quality , *CHEMICAL inhibitors - Abstract
A methodology for the determination of inhibitors in raw milk through turbidimetry signs was evaluated by means of the Diramic System. For this, the control microorganism Bacillus stearothermophilus ATCC 10149 was used. It was proved that the method has a higher sensitivity than the yogurt test, having a repeatibility variation coefficient lower than 3%, with a reading time of two and a half hours. With these new methodologies, the use of the Diramic System is widen in the evaluation of milk quality. [ABSTRACT FROM AUTHOR]
- Published
- 2006
26. COMPARACIÓN DE INHIBIDORES COMERCIALES Y OBTENIDOS DE PRODUCTOS DE DESECHO Y NATURALES NACIONALES.
- Author
-
Armaignaic, Elaine Ojeda and Cortón, Romelia Hing
- Subjects
- *
CHEMICAL inhibitors , *CORROSION & anti-corrosives , *CASUARINA , *ACIDS , *CARBON steel , *STAINLESS steel , *COPPER - Abstract
The present work is an answer to the necessity of determining the effectivity of three corrosion inhibitors, such as Corromin E2, mosto or vinaza and Casuarina e liquid extracts in alkaline, neuter and acid mediums, with the purpose of being used for the different systems at these conditions of pH (3, 6 y 9) at environment temperature. It is analyzed the velocity of corrosion of the metallic materials, carbon steel (CT3KP), stainless steel (12X18H10T) and copper (Cu:99.98 %, Zn: 0.01 %, Ni: 0.005 %. Pb: 0.005 %); such as the efficiencies of the inhibitors under the conditions of work previously mentioned. The method used was the potentiostatic. They are presented graphics where can be observed the behaviors of the materials and tendencies of the inhibitors, such as tables that show the results obtained during the investigation . Finally, it is concluded which is the best inhibitor for each one of the different mediums and materials analyzed. [ABSTRACT FROM AUTHOR]
- Published
- 2006
27. Respuesta inmunomoduladora de la superóxido dismutasa en juveniles de camarón blanco (Litopenaeus vannamei) expuestos a inmunoestimulantes.
- Author
-
Campa-Córdova, A. I., Hernández-Saavedra, N. Y., Aguirre-Guzmén, G., and Ascencio, F.
- Subjects
- *
IMMUNOLOGICAL adjuvants , *IMMUNOMODULATORS , *IMMUNOREGULATION , *MANGANESE , *MANGANESE enzymes , *SUPEROXIDE dismutase , *ANTIOXIDANTS , *CHEMICAL inhibitors , *PATHOGENIC bacteria , *PENAEUS subtilis - Abstract
Immunomodulatory action of manganese superoxide dismutase (Mn-SOD) in juvenile American white shrimp (Litopenaeus vannamei) was studied. Shrimp between 0.7 and 1.0 g were immersed in aerated ß-glucan, lipopolysaccharide (LPS), fucoidan, and heat-killed Vibrio penaeicida solutions for 6 h. The enzymatic activity of Mn-SOD in entire organisms was investigated to evaluate whether different immunostimulants were able to induce antioxidant activity. The immunostimulants tested activated the immune system in juvenile shrimp and the highest antioxidant response was observed 48 h after the challenge with ß-glucan, LPS, fucoidan and heat-killed V. penaeicida. The bacterin caused 3.2 times more Mn-SOD activity than the control group. Immunostimulated shrimp were challenged with live V. penaeicida on the tenth day and a second antioxidant response was observed 48 h after exposure to live pathogenic bacteria. Immunostimulated shrimp with ß-glucan showed the highest Mn-SOD response (2.5 times more than the control group). This study showed the capacity of juvenile shrimp to enhance antioxidant response during a challenge with pathogenic bacteria after exposure to immunostimulants. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
28. EL chocolate o los beneficios de un antioxidante (una historia real).
- Author
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Hernández, Jorge Castillo
- Subjects
- *
CHOCOLATE , *ANTIOXIDANTS , *CHEMICAL inhibitors , *HEALTH , *COCOA products - Abstract
Chocolate is both temptation and resistance, it is an actual need of the palate and the mood, and of course an unreflective craving; however we must try to understand that it is an excellent source of antioxidant, with the positive result in the strength of our health. Far better than wine and tea, the chocolate is a sweet alternative to obtain antioxidant mechanisms that benefit our cells and their function. In the next paragraphs we will try to establish the benefits gained with the frequent consumption of chocolate. [ABSTRACT FROM AUTHOR]
- Published
- 2004
29. ESTUDIO DE LA CORROSIÓN EN EL CIRCUITO DEL TOPE DE LA TORRE DE DESTILACIÓN ATMOSFÉRICA DE LA REFINERÍA "HNOS. DÍAZ.".
- Author
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Armaignac, Elaine Ojeda, Cortón, Romelia Hing, and Bergues, Marcos Maura
- Subjects
- *
CORROSION & anti-corrosives , *CARBON steel , *CHROMIUM , *PETROLEUM refineries , *CHEMICAL inhibitors - Abstract
The present work presents a study of the corrosion behavior of carbon steel and chromium steel at the circuit of the top of the atmospherical distillation tower in the "Hnos Díaz" Refinery, and the effectivity of a corrosion inhibitor such as Chemadd H8H10F. It was used theweight loss method for corrosion rates calculations, and are presented the tables with the results and the statisties analysis of these. The conclusions present which is the most adecuated material for these conditions and the inhibitor concentration recommended. The work presents some recommendations that promove the diminution of the corrosion rates in this system. [ABSTRACT FROM AUTHOR]
- Published
- 2004
30. EVALUACIÓN DE INHIBIDORES DE CORROSIÓN.
- Author
-
Hing Cortón, Romelia, Ojeda Armaignac, Elaine, and Rodríguez Viamontes, Katia
- Subjects
- *
CORROSION & anti-corrosives , *CHEMICAL inhibitors , *ACIDS , *METALS , *TEMPERATURE - Abstract
The present work responds to the necessity of determining the effectiveness of two corrosion inhibitors, Corromín E2 and Chemadd H810F, in acid, neuter and alkaline medium, with the purpose of being used for different systems at these conditions of (3; 6 and 9) and temperature (50°C). It was determined the corrosion rate of four metallic materials (steel 20, 08X13, 12X18H10T and monel) making use of the inhibitors mentioned above, so as the efficiency of the inhibitors. The method of the loss weight was used, and two charts present all the results obtained during the research. The conclusions to which we arrived indicate which is the best inhibitor and the adequate concentration for each one of the different mediums and materials. [ABSTRACT FROM AUTHOR]
- Published
- 2003
31. Efecto del tratamiento con microondas e inhibidores en el oscurecimiento enzimático y carotenoides de plátano macho.
- Author
-
Torre Marina, Ma. Covadonga
- Subjects
- *
HEAT , *PHYSICS , *MICROWAVES , *ENZYME inhibitors , *CHEMICAL inhibitors , *CHEMICALS , *ENZYMATIC analysis , *ANALYTICAL chemistry , *DYNAMICS - Abstract
The object of this study is to evaluate the effect of heat treatment by microwaves and the use of some chemical inhibitors on the enzymatic activity of the poliphcnoloxidase of plantain (Musa paradisiaca L.). During the experimental phase the IN VITRO effect will be determined through specific enzymatic kinetics. The enzyme will be extracted and purified from the pulp. Based on the obtained results the best inhibition conditions will be selected and will be applied directly to plantain slices simulating the industrial treatment. Plantain represents the principal source of energy in certain subsistence diets. It is a good source of potassium and Β-carotene and a respectable source of fiber and vitamin C. Β-carotene, apart from being the carotenoid of greater vitaminic activity (it consists of two molecules of vitamin A), has antioxidant properties; this is the reason why it is important to extract, quantify and evaluate the effect heat treatment by microwaves, frying and the use of inhibitors have on it. HPLC will be used for this effect. The search for new alternatives to avoid the browning of plantain arises from the need to substitute sulfites. In 1985, it was concluded that they were safe for most people, however they represent an unpredictable and severe risk for asthmatic people and for those who are sensitive to these preservatives. It must be said that any person may develop sulfite sensitivity at any stage of his life. The physiological response brought upon by sulfites may go from breathing difficulty and rash, to breathing and heart failure. Since one of the alternative uses of the production plantain surplus, is as chips commercialized as snacks, they are consumed mainly by children; this must be considered as a limitation for the use of additives according to the joint established regulations of FAO and CODEX ALIMENTARIUS. [ABSTRACT FROM AUTHOR]
- Published
- 2002
32. EVALUACIÓN DE LA EFECTIVIDAD DEL G-0 COMO INHIBIDOR DE LA CORROSIÓN GALVÁNICA DEL PAR ACERO - COBRE EN HCl AL 5 % PESO.
- Author
-
Bermúdez, Xiomara Cabrera and Jacomino, Olga Cortijo
- Subjects
- *
ELECTROLYTIC corrosion , *CORROSION & anti-corrosives , *CHEMICAL inhibitors , *ACIDS , *TEMPERATURE , *STEEL , *COPPER - Abstract
In this paper it is made the evaluation of G-0's effectiveness as a corrosion inhibitor of carbon steel in contact with copper, using solutions of 5 % HCl at boiling temperature. This evaluation is done using the gravimetric method of evaluation of the corrosion rate and the determination of the galvanic current produced by this pair. It was found that the evaluated product is an adequate steel corrosion and it is not copper´s corrosion inhibitor. It offers 82,7 % of protection. Besides that, it was found that the obtained results correspond in both used ways with the results that appear in the literature about galvanic corrosion. [ABSTRACT FROM AUTHOR]
- Published
- 2000
33. Ajuste y control de los regímenes químicos en los sistemas termoenergéticos del CIGB.
- Author
-
Zaballa, Rebeca Vizcaíno, Mariño, Joel Alfonso, Pérez, Rodolfo Castillo, Gutiérrez, Josefina Astorga, Del Moral, Carlos, and Montané, Manuel
- Subjects
- *
FEED-water , *FEED-water purification , *WATER towers , *CORROSION & anti-corrosives , *CHEMICAL inhibitors - Abstract
In the circuits of heat and cold the water is used like vehicle of transmission of temperature and exchanger agent of heat. However, the water occasions serious problems: deteriorates the circuits with precipitations of magnesic and calcic salts, that adhere to the walls of the equipment. These scales reduce the thermal transmission making diminish the energetical humiliation, and they oxidize the metallic parts of the circuits, accelerating their degradation for effect of the corrosion. This phenomenon is sometimes, so alarming that has been denominated the cancer of the industry. An ideal solution that impedes the formation of scales and the corrosion of the circuits, consists in dosing chemical appropriate products in the systems of boiler water steam and cooling water towers. [ABSTRACT FROM AUTHOR]
- Published
- 1999
34. Inhibidores de la bomba de protones (IBP). ¿Serán los únicos?
- Author
-
González González, José Alberto
- Subjects
- *
PROTON pump inhibitors , *ENZYME inhibitors , *GASTRIC acid , *CHEMICAL inhibitors - Abstract
El artículo analiza el uso de los inhibidores de la bomba de protones (IBP). Se inició el uso de estos inhibidores en forma clínica en Europa hace 15 años y en los Estados Unidos hace 10 años. Se menciona que al principio, la posibilidad de provocar tumoraciones gástricas preocupó fuertemente a los investigadores. El artículo también discute las diferencias en cuanto al uso de IBP versus bloqueadores H2 en el tratamiento de pacientes con enfermedades pépticas.
- Published
- 2001
35. Correction.
- Subjects
- *
PUBLISHING , *ENZYME inhibitors , *ANTIMALARIALS , *DRUG design , *CHEMICAL inhibitors - Published
- 2012
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