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Biomedical subjects

Francisco J Morales

Publications and source records attributed to Francisco J Morales.

13 recordsLinked to original sources
PubMed2007

Tropical Whitefly IPM Project.

The Tropical Whitefly IPM Project (TWFP) is an initiative of the Systemwide IPM Programme of the Consultative Group on International Agricultural Research (CGIAR), financed by the Department for International Development (DFID) of the United Kingdom, the Danish International Development Agency (DANIDA), the United States Department of Agriculture (USDA) and Agency for International Development (USAID), the Australian Centre for International Agricultural Research (ACIAR), and the New Zealand Agency for International Development (NZAID), to manage whitefly pests and whitefly-transmitted viruses in the Tropics. Participating CGIAR and other international centers include the Centre for International Tropical Agriculture (CIAT); the International Institute of Tropical Agriculture (IITA); The International Potato Centre (CIP); the Asian Vegetable Research and Development Centre (AVRDC); and the International Centre of Insect Physiology and Ecology (ICIPE), in close collaboration with the National Resources Institute (NRI-UK); national agricultural research institutions; agricultural universities; and advanced agricultural research laboratories in Africa, Asia, Europe, the Pacific Region, and the Americas. The TWFP was launched in 1996 as five separate but closely linked subprojects targeting: (1) Bemisia tabaci as a vector of viruses affecting cassava and sweet potato in sub-Saharan Africa (IITA, NRI, CIP, CIAT); (2) B. tabaci as a vector of viruses in mixed cropping systems of Mexico, Central America, and the Caribbean (CIAT); (3) B. tabaci as a vector of viruses in mixed cropping systems of eastern and southern Africa (ICIPE, AVRDC); (4) B. tabaci as a vector of viruses in mixed cropping systems of Southeast Asia (AVRDC); (5) Trialeurodes vaporariorum as a pest in mixed cropping systems of the Andean highlands (CIAT); and (6) whiteflies as pests of cassava in South America (CIAT). Diagnostic surveys conducted in Phase I (1997-2000) clearly showed that the two main whitefly pests in the Tropics are B. tabaci and, in the highlands, T. vaporariorum. Other whitefly species investigated by the TWFP included B. afer and Aleurotrachelus socialis. B. tabaci is the main vector of plant viruses inducing African cassava mosaic disease, sweet potato virus disease, bean golden mosaic disease, and many other diseases of horticultural crops, mainly tomato, hot and sweet peppers, squash, melon, and several other cucurbits. Genetic resistance was identified as the most important component of an IPM programme, followed by phytosanitary, cultural and legal measures. The two most important factors contributing to whitefly/virus epidemics were shown to be pesticide abuse and the use of virus-infected planting materials. Biological control is only effective in cropping systems with minimal or rational use of insecticides, and should be considered only as a complementary IPM strategy. Farmer education and technical assistance are considered the most critical steps toward the implementation of sustainable and economically viable IPM strategies in tropical countries affected by whitefly pests and whitefly-transmitted viruses.

Animals↗
PubMed2006

Documented exercise-induced cardiac arrest in a paediatric patient with hypertrophic cardiomyopathy.

A paediatric patient with hypertrophic cardiomyopathy (HCM) presented cardiac arrest due to ventricular fibrillation. Ventricular arrhythmias were not induced in an electrophysiological study, but an implantable cardioverter defibrillator (ICD) was implanted. Nine months later, the child experienced a recurrence of cardiac arrest during exercise, which was successfully treated with a defibrillator shock from the device. Analysis of the stored electrograms demonstrated ventricular fibrillation of abrupt onset following sinus tachycardia. The risk factors and the potential mechanism leading to recurrent cardiac arrest in this case are discussed. This report supports implantation of an ICD as a life-saving therapeutic approach not only for adults but also for children with HCM at high risk.

Cardiomyopathy, Hypertrophic↗
PubMed2006

Study on fluorescence of Maillard reaction compounds in breakfast cereals.

During the advanced stage of the Maillard reaction (MR) in food processing and cooking, Amadori rearrangement products undergo dehydration and fission and fluorescent substances are formed. Free and total (free + linked to the protein backbone) fluorescence (FIC) due to Maillard compounds in 60 commercial breakfast cereals was evaluated. Pronase was used for efficient release of linked fluorescent Maillard compounds from the protein backbone. Results were correlated with some heat-induced markers of the extent of the MR or sugar caramelisation during cereal processing, such as hydroxymethylfurfural, furfural, glucosilisomaltol and furosine. The effect of sample composition (dietary-fibre added, protein, etc.) on levels of FIC, expressed as fluorescence intensity (FI) per milligram of sample, is discussed. FIC is significantly correlated to the protein content of the sample and fluorescent Maillard compounds are mainly linked to the protein backbone. The ratio of total-FIC to free-FIC was 10.4-fold for corn-based, wheat-based and multicereal-based breakfast cereals but significantly higher in rice-based samples. Addition of dietary fibre or honey increased the FIC values. Data support the usefulness of FIC measurement as an unspecific heat-induced marker in breakfast cereals.

Dietary Fiber↗
PubMed2006

Relationship between acrylamide and thermal-processing indexes in commercial breakfast cereals: a survey of Spanish breakfast cereals.

Breakfast cereals are significant contributors to the daily intake of food-derived acrylamide in Western countries. Acrylamide was determined by LC-MS in 60 commercial breakfast cereals marketed in Spain. Several SPE cartridges were evaluated for clarification of the aqueous extract. LOQ was 62 microg/kg . Acrylamide content ranged from < 62-803 microg/kg (average 292 microg/kg , and median 258 microg/kg , with an estimated acrylamide intake from breakfast cereals of 2.68 microg acrylamide/person/day. According to the German concept of minimization, a signal value 450 microg/kg was calculated. Relationships among acrylamide and some parameters of the studied samples such as type of cereal, its physical form (puffed and flaked) or certain ingredients in the formulation (proteins and dietary fibre content) were also investigated. Wheat-based cereals contained significantly higher levels of acrylamide, as did samples with higher fibre or protein content. In addition, puffed breakfast cereals also contained significantly higher levels of acrylamide. There was no significant correlation between acrylamide levels and contents of 5-hydroxymethylfurfural, furosine or cereal browning.

Acrylamide↗
PubMed2005

Assessing the antioxidant activity of melanoidins from coffee brews by different antioxidant methods.

Antioxidant activity of instant coffees produced from the same green coffee beans roasted at three different degrees was analyzed. Coffee melanoidins were obtained by ultrafiltration (10 kDa cutoff) and subsequent diafiltration. Pure melanoidins were isolated from melanoidins after overnight incubation in 2 M NaCl and then ultrafiltered. Filtrates, corresponding to the low molecular weight (LMW) fraction noncovalently linked to the melanoidin skeleton, were also preserved. Antioxidant activity of coffee brews (CB), melanoidins (M), pure melanoidins (PM), and bounded melanoidin compounds (BMC) were tested using the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing power (FRAP) methods. The correlation between the different methods was studied. The higher contribution of melanoidins to the total antioxidant activity of coffees was shown to be caused by the LMW compounds linked noncovalently to the melanoidin skeleton, as data from BMC confirmed. CB, M, and BMC fractions exert the highest antioxidant activity in aqueous media, whereas PM was not dependent on the reaction media. The highest correlation was found between DPPH and FRAP methods.

Antioxidants↗
PubMed2005

Unraveling the contribution of melanoidins to the antioxidant activity of coffee brews.

Instant coffees produced from the same green coffee beans were supplied from a company in different roasting degrees, light, medium, and dark. Melanoidins were obtained by ultrafiltration (10 kDa) and subsequent diafiltration. Pure melanoidins were isolated from melanoidins after overnight incubation in 2 M NaCl. The antioxidant activities of instant coffees, melanoidins, and pure melanoidins were tested using the conjugated diene formation from a 2,2'-azobis(2-amidinopropane) dihydrochloride-induced linoleic acid oxidation in an aqueous system. No significant differences were found between melanoidins and pure melanoidins with different roasting degrees. Therefore, the contribution of the pure melanoidin fraction to the total antioxidant activity of melanoidins was significantly lower. More than 50% of the antioxidant activity of melanoidins is due to low molecular weight compounds linked non-covalently to the melanoidin skeleton. A new concept of the overall antioxidant properties of food melanoidins is described, where chelating ability toward low molecular weight antioxidant compounds is connected to the stabilization of these compounds involved in the shelf life of the product.

Amidines↗
PubMed2004

Emerging infectious diseases of plants: pathogen pollution, climate change and agrotechnology drivers.

Emerging infectious diseases (EIDs) pose threats to conservation and public health. Here, we apply the definition of EIDs used in the medical and veterinary fields to botany and highlight a series of emerging plant diseases. We include EIDs of cultivated and wild plants, some of which are of significant conservation concern. The underlying cause of most plant EIDs is the anthropogenic introduction of parasites, although severe weather events are also important drivers of disease emergence. Much is known about crop plant EIDs, but there is little information about wild-plant EIDs, suggesting that their impact on conservation is underestimated. We conclude with recommendations for improving strategies for the surveillance and control of plant EIDs.

Journal Article↗
PubMed2004

The ecology and epidemiology of whitefly-transmitted viruses in Latin America.

Whitefly-transmitted geminiviruses are the most important constraint to the production of common bean and vegetable crops in the tropical lowlands and mid-altitude valleys of Latin America. Currently, over 30 distinct species of geminiviruses that are transmitted by the whitefly Bemisia tabaci infect common bean, tomato, pepper, cucurbits and other horticultural crops. A climate probability model (using FloraMap) was obtained using data from 304 geo-referenced locations where B. tabaci and geminiviruses cause significant damage. Clustering of the 304 points produced a simple model with two climatic variables: a dry season of at least 4 months each with less than 80 mm of rain and a mean temperature of the hottest month exceeding 21 degrees C. A modified Koeppen climate classification showed that 55% of the geminivirus-affected localities are in the tropical wet/dry region, 22% in the tropical and subtropical dry/humid climates and the remaining locations belonged to the wet equatorial and trade wind litoral climates. These findings contribute to understanding whitefly/geminivirus epidemics and implementation of sustainable integrated pest and disease management practices.

Animals↗
PubMed2002

Melanoidins exert a weak antiradical activity in watery fluids.

The Maillard reaction has a dramatic impact on the overall acceptance and nutritional quality of most of the foods consumed daily in European countries. Melanoidins are polymeric structures formed in the last stage of the Maillard reaction with nearly unknown effect on the human health. The antiradical activity of several melanoidins isolated from model systems and coffee has been studied. A novel antiradical efficiency concept has been applied to describe the antiradical activity in an aqueous medium by bleaching the radical cation N,N-dimethyl-p-phenylenediamine (DMPD(*)(+)). Melanoidins exerted a significantly lower antiradical activity than classical antioxidant compounds (tannic acid, ferrulic acid, caffeic acid, gallic acid, and Trolox) in an aqueous medium. Significant differences have been observed according to the type of amino acid used as reactant during the formation of the melanoidin structure and the antiradical efficiency exerted.

Antioxidants↗
PubMed2002

Antiradical efficiency of Maillard reaction mixtures in a hydrophilic media.

The Maillard reaction (MR) has a clear impact in food science, nutrition, and medical research. Free radical scavenging capacities of several MR mixtures made from single combinations of glucose or lactose and amino acids (gly, his, lys, trp, met, and cys) were evaluated by using the N,N-dimethyl-p-phenylenediamine radical cation assay. Medium-roasted coffee brew was used as reference of a thermally processed food. A novel approach has been applied in order to get more information about the kinetic behavior of the radical scavenging properties of MR mixtures in a watery environment. Antiradical efficiency (AE) concept has been applied, and it takes into consideration the reaction time, apart from the amount of antioxidant necessary to decrease by 50% the radical initial concentration (EC(50)). Cysteine and histidine reveal as powerful amino acids to exert a high AE in the MR mixtures. No relationship between AE parameter and browning was observed.

Amino Acids↗
PubMed2002

Deceleration time of early filling in patients with left ventricular systolic dysfunction: functional and prognostic independent value.

BACKGROUND: Although diastolic function parameters have been mentioned as significant predictors of functional capacity and prognosis in patients with left ventricular (LV) systolic dysfunction, it has not been fully elucidated whether they keep an independent predictive value when multiple parameters from a wide variety of examinations are considered. METHODS: We prospectively studied 60 patients with New York Heart Association (NYHA) class II-IV chronic heart failure symptoms and LV ejection fraction <0.4. At the time of entry into the study, demographic data and functional class were obtained, and usual Doppler echocardiographic, radionuclide ventriculographic, cardiopulmonary exercise testing and hemodynamic variables were determined. Deceleration time of early filling (DT) and NYHA functional class were the only independent predictors of functional capacity as assessed by means of peak oxygen uptake (peak VO2). Mean follow-up was 21 +/- 6 months, and event-free survival was defined as the absence of cardiac death, urgent cardiac transplantation, or hospital admission requiring inotropic or mechanical support. RESULTS: Multivariate Cox analysis showed that DT (P =.008), peak VO2 (P =.01), and NYHA class (P =.02) were independent predictors of event-free survival at 1 year. Patients in the lowest tertile of DT (<130 ms) had a significantly lower event-free survival than patients in the intermediate (44% vs 80%, P =.03) and in the highest tertile (44% vs 83%, P =.02). Patients with both a DT <130 milliseconds and a peak VO2 <14 mL/kg/min had the highest rate of events at 1 year (83% vs 22% for the remaining patients, relative risk 3.75, P <.001). CONCLUSIONS: In patients with LV systolic dysfunction, DT is a powerful independent predictor of functional capacity and prognosis among a wide variety of variables. A shortened DT (<130 ms) identifies a subgroup of patients with a worse outcome, especially when combined with a reduced peak VO2 (<14 mL/kg/min).

Aged↗
PubMedDate not supplied

Application of a fast high-performance liquid chromatography method for simultaneous determination of furanic compounds and glucosylisomaltol in breakfast cereals.

The high-performance liquid chormatography method reported in the present paper provides a fast, low-cost, precise, and simple technique to analyze simultaneously 3 different indicators of nonenzymatic browning, i.e., hydroxymethylfurfural (HMF), furfural, and glucosylisomaltol (GIM), in breakfast cereals. These compounds were extracted in aqueous solution and separated on a reversed-phase C18 column with water-acetonitrile (95 + 5, v/v) mobile phase under isocratic conditions. Average recovery rates for HMF, furfural, and GIM were 99.1, 98.4, and 99.4%, respectively. The coefficients of variation were 3.67, 2.42, and 1.59% for HMF, furfural, and GIM, respectively. The detection limit was 0.01 mg/kg, and the quantitation limit was 0.05 mg/kg for the 3 studied compounds.

Acetonitriles↗