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1.
Heliyon ; 10(11): e32150, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38873677

ABSTRACT

Food industry is increasingly using functional ingredients to improve the food product quality. Lipid-containing functional ingredients are important sources of nutrients. This review examines the current state of emulsification and stabilisation technologies for incorporating lipophilic functional ingredients into food systems. Lipophilic functional ingredients, such as omega-3 fatty acids, carotenoids, and fat-soluble vitamins, offer numerous health benefits but present challenges due to their limited solubility in water-based food matrices. Emulsification techniques enable the dispersion of these ingredients in aqueous environments, facilitating their inclusion in a variety of food products. This review highlights recent advances in food emulsion formulation, emulsification methods and stabilisation techniques which, together, improve the stability and bioavailability of lipophilic compounds. The role of various emulsifiers, stabilizers, and encapsulation materials in enhancing the functionality of these ingredients is also explored. Furthermore, the review discusses different stabilisation techniques which can yield in emulsion in a solid or liquid state. By providing a comprehensive overview of current technologies, this review aims to guide future research and application in the development of functional foods enriched with lipophilic ingredients.

2.
Heliyon ; 9(11): e21499, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38027781

ABSTRACT

High-oleic palm oil is a food-grade oil with desirable properties, as it is characterised by having an oleic acid concentration above 50 % and a high vitamin E and provitamin A content. This study investigated the effect of different combinations of two wall materials (whey protein (WP) and Capsul®, a commercial octenyl succinic anhydride modified starch (OSA-MS)) on the concentration of provitamin A, vitamin E and oleic acid, and the physical properties of high oleic palm oil emulsions encapsulated by Refractance Window drying technology. Wall material composition significantly affected (p < 0.05) all response variables, and R2 values were above 0.75 for all responses. Phytonutrient preservation showed its highest at an OSA-MS: WP concentration ratio of 1: 3. Optimal results were achieved (minimum moisture content, water activity and hygroscopicity, and maximum encapsulation efficiency and phytonutrient preservation) at an OSA-MS concentration of 8.13 % and WP concentration of 91.87 %. Flakes were obtained as a solid structure that protects oil's phytonutrients with 94 %, 75 % and 87 % of preservation of oleic acid, vitamin E and carotenoids, respectively. It shows that the wall material combination and encapsulation technique are suitable for obtaining lipophilic functional compounds.

3.
Heliyon ; 9(8): e18418, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37520949

ABSTRACT

Light-absorbing carbonaceous particles (LAC) may cause and/or exacerbate non-communicable diseases, interfere with the Earth's radiative balance, darken urban buildings and impair vistas. In this study, we explored the temporal behaviour of LAC concentrations measured at wavelengths of 370 nm (brown carbon, BrC) and 880 nm (black carbon, BC) at two sites of a mid-sized city in Brazil. We observed sharp changes in LAC concentrations at the city centre site in response to variations in traffic volume. The highest concentrations were observed when winds originated from both the city core and from the direction of the bus terminal. The suburban site exhibited a notably uniform diurnal pattern and consistently lower LAC concentrations throughout the day. Nevertheless, substantial increases during the evening led to mean BrC and BC concentrations (2.6 and 2.2 µg m-3, respectively) comparable to daytime peaks observed in the city centre (3 µg m-3 and 2.5 µg m-3). This phenomenon was attributed to the burning of residential waste and overgrown vegetation in nearby vacant lots. Moreover, the highest concentrations coincided with periods of low wind speeds, usually linked to non-buoyant plumes from point sources. BrC concentrations surpassed BC concentrations, even at the city centre site. Not only was the Ångström absorption exponent (Å370/880) larger at the suburban site compared to the city centre (95th percentiles of 1.73 and 1.38, respectively), but it also exhibited a wider span. Overall, the combined LAC and Å370/880 data indicated that i) biomass burning is a major source of LAC at the suburban site; ii) at the city centre, bare BC particles may become internally mixed with BrC from biomass or fossil fuel emissions and enhance absorption at lower wavelengths. The occurrence of LAC peaks outside the evening rush hours suggests that other sources but on-road vehicular emissions may contribute to the deterioration of the air quality in the urban core. Tackling air quality across the urban perimeter requires targeting other potential sources but traffic emissions.

4.
PLoS Comput Biol ; 18(10): e1010674, 2022 10.
Article in English | MEDLINE | ID: mdl-36315576

ABSTRACT

Microbial consortia are an exciting alternative for increasing the performances of bioprocesses for the production of complex metabolic products. However, the functional properties of microbial communities remain challenging to control, considering the complex interaction mechanisms occurring between co-cultured microbial species. Indeed, microbial communities are highly dynamic and can adapt to changing environmental conditions through complex mechanisms, such as phenotypic diversification. We focused on stabilizing a co-culture of Saccharomyces cerevisiae and Escherichia coli in continuous cultures. Our preliminary data pointed out that transient diauxic shifts could lead to stable co-culture by providing periodic fitness advantages to the yeast. Based on a computational toolbox called MONCKS (for MONod-type Co-culture Kinetic Simulation), we were able to predict the dynamics of diauxic shift for both species based on a cybernetic approach. This toolbox was further used to predict the frequency of diauxic shift to be applied to reach co-culture stability. These simulations were successfully reproduced experimentally in continuous bioreactors with glucose pulsing. Finally, based on a bet-hedging reporter, we observed that the yeast population exhibited an increased phenotypic diversification process in co-culture compared with mono-culture, suggesting that this mechanism could be the basis of the metabolic fitness of the yeast.


Subject(s)
Glucose , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolism , Coculture Techniques , Glucose/metabolism , Bioreactors , Computer Simulation , Escherichia coli/metabolism
5.
Antibiotics (Basel) ; 10(6)2021 May 21.
Article in English | MEDLINE | ID: mdl-34063846

ABSTRACT

There is an urgent need for the development of new antibiotics. Here, we describe the inhibitory activity of new quinone compounds against methicillin-resistant Staphylococcus aureus (ATCC® 43300), methicillin-sensitive S. aureus (ATCC® 29213), and two clinical isolates from Chile (ISP-213 and ISP-214). We observed 99.9% reduction in viability within 2 h of exposure without the cultures exhibiting any post-antibiotic effect, which was twice the kinetics to that observed with vancomycin. These clinical isolates did not acquire resistance to these quinone derivatives during the course of our study. We found that these compounds protected larvae of the greater wax moth, sp. Galleria mellonella, from infection by these MRSA clinical strains as effectively as vancomycin. These quinone derivatives are potential drug candidates worth further development.

6.
Food Res Int ; 141: 110141, 2021 03.
Article in English | MEDLINE | ID: mdl-33642008

ABSTRACT

This study evaluated the effects of different roasting profiles (time/temperature) and brewing methods on the physicochemical and sensory characteristics of coffee brews. Cold brewing (dripping and immersion) and hot brewing (French press) methods were studied to understand the effects of water temperature and technical brewing method conditions on the chemical compound extraction in coffees roasted at high-temperature short time (HTST) and low-temperature long time (LTLT). The results showed that coffee beverages were clearly differentiated concerning the roasting profile when hot water was used (90 ± 3 °C) in brewing. Separation of beverages according to the water temperature used in brewing was observed. Notably, hot brewing coffees were distinguished from cold brewing (19 ± 2 °C) based on a higher titratable acidity and abundance of some furan compounds. The non-volatile extraction rate increased at higher brewing temperatures. At the same brewing temperature, dripping exhibited a higher extraction rate than immersion brewing, which suggests that the coffee extraction process is affected by the design and operation of the cold brewing system. Coffee beverages brewed with HTST and cold dripping displayed the highest value in total dissolved solids (TDS), extraction yield, as well as the highest caffeine, trigonelline, 4- and 5-caffeoylquinic acids (CQAs) contents. Regardless of the roasting profile, coffees brewed by cold dripping were perceived with more bitter and roasted flavors. In contrast, cold immersion and hot coffee beverages showed remarkable sweetness, nutty, caramel, and malt attributes. In turn, these attributes showed an inverse correlation with caffeine concentration, trigonelline, CQAs, and TDS. The findings of this study demonstrate that volatile and non-volatile compounds present in roasted coffee depend on time-temperature roasting conditions; in turn, their presence in the resulting beverages are related to the extraction of the operational conditions of coffee brewing methods.


Subject(s)
Coffea , Coffee , Caffeine/analysis , Hot Temperature , Taste
7.
Sci Rep ; 9(1): 8440, 2019 06 11.
Article in English | MEDLINE | ID: mdl-31186459

ABSTRACT

The effects of grinding (medium-coarse) and extraction time (14-22 h) on the physicochemical and sensorial properties of cold brew coffee produced using two types of Colombian specialty coffees (Huila and Nariño) were evaluated. Cold coffee brewed under coarse grinding and 22 h of extraction exhibited the highest values of total dissolved solids, extraction yield, pH, titratable acidity (TA), and total phenolic content. The type of coffee used mainly affected the TA and pH. All cold brew coffee samples had lower TA values than their hot counterparts. Nariño cold brew samples had higher TA values than those of Huila in all treatments evaluated. Higher scores were reported in the sensorial evaluation of cold brew coffee when prepared using the shortest time (14 h) and coarse grinding for both coffee types. These coffees were characterized by strong sweetness, fruity and floral flavours, medium bitterness and acidity, and a creamy body. Furans, pyrazines, ketones, aldehydes, pyrroles, esters, lactones, furanones, and phenols were detected as odour-active compounds. The findings of this study demonstrate that the particle size, contact time, and coffee type affect the physicochemical and sensorial characteristics of cold brew coffee, leading to cold brew coffees with different flavour profiles.


Subject(s)
Coffea , Coffee , Odorants/analysis , Taste , Cooking/methods , Flavoring Agents/chemistry , Food Handling/methods , Humans
8.
Sci Rep ; 9(1): 5625, 2019 04 04.
Article in English | MEDLINE | ID: mdl-30948743

ABSTRACT

The purpose of this work was to model the survival of the microorganism and the kinetics of drying during the encapsulation of Lactobacillus fermentum K73 by Refractance Window drying. A whey culture medium with and without addition of maltodextrin were used as encapsulation matrices. The microorganism with the encapsulation matrices was dried at three water temperatures (333, 343 and 353 K) until reaching balanced moisture. Microorganism survival and thin layer drying kinetics were studied by using mathematical models. Results showed that modified Gompertz model and Midilli model described the survival of the microorganism and the drying kinetics, respectively. The most favorable process conditions found with the mathematical modelling were a drying time of 2460 s, at a temperature of 353 K. At these conditions, a product with 9.1 Log CFU/g and a final humidity of 10% [wet basis] using the culture medium as encapsulation matrix was obtained. The result shows that Refractance Window can be applied to encapsulate the microorganism probiotic with a proper survival of the microorganism.


Subject(s)
Cell Encapsulation/methods , Limosilactobacillus fermentum/metabolism , Limosilactobacillus fermentum/physiology , Desiccation/methods , Freeze Drying/methods , Humidity , Microbial Viability , Models, Theoretical , Probiotics , Temperature , Whey Proteins
9.
BMC Syst Biol ; 12(1): 102, 2018 11 12.
Article in English | MEDLINE | ID: mdl-30419897

ABSTRACT

BACKGROUND: Classic metabolic engineering strategies often induce significant flux imbalances to microbial metabolism, causing undesirable outcomes such as suboptimal conversion of substrates to products. Several mathematical frameworks have been developed to understand the physiological and metabolic state of production strains and to identify genetic modification targets for improved bioproduct formation. In this work, a modeling approach was applied to describe the physiological behavior and the metabolic fluxes of a shikimic acid overproducing Escherichia coli strain lacking the major glucose transport system, grown on complex media. RESULTS: The obtained flux distributions indicate the presence of high fluxes through the pentose phosphate and Entner-Doudoroff pathways, which could limit the availability of erythrose-4-phosphate for shikimic acid production even with high flux redirection through the pentose phosphate pathway. In addition, highly active glyoxylate shunt fluxes and a pyruvate/acetate cycle are indicators of overflow glycolytic metabolism in the tested conditions. The analysis of the combined physiological and flux response surfaces, enabled zone allocation for different physiological outputs within variant substrate conditions. This information was then used for an improved fed-batch process designed to preserve the metabolic conditions that were found to enhance shikimic acid productivity. This resulted in a 40% increase in the shikimic acid titer (60 g/L) and 70% increase in volumetric productivity (2.45 gSA/L*h), while preserving yields, compared to the batch process. CONCLUSIONS: The combination of dynamic metabolic modeling and experimental parameter response surfaces was a successful approach to understand and predict the behavior of a shikimic acid producing strain under variable substrate concentrations. Response surfaces were useful for allocating different physiological behavior zones with different preferential product outcomes. Both model sets provided information that could be applied to enhance shikimic acid production on an engineered shikimic acid overproducing Escherichia coli strain.


Subject(s)
Escherichia coli/genetics , Escherichia coli/metabolism , Models, Biological , Shikimic Acid/metabolism , Biological Transport/genetics , Carbon/metabolism , Escherichia coli/growth & development , Glucose/metabolism , Metabolic Engineering , Metabolic Flux Analysis
10.
Forensic Sci Int Genet ; 21: 76-80, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26736138

ABSTRACT

We analyzed the Y chromosome haplotypes (Yfiler) of 978 non-related Chilean males grouped in five sampling regions (Iquique, Santiago de Chile, Concepción, Temuco and Punta Arenas) covering main geo-political regions. Overall, 803 different haplotypes and 688 singletons were observed. Molecular diversity was moderately lower than in other neighboring countries (e.g. Argentina); and AMOVA analysis on Y-STR haplotypes showed that among variation within Chile accounted for only 0.25% of the total variation. Punta Arenas, in the southern cone, showed the lowest haplotype diversity, and discrimination capacity, and also the highest matching probability of the five Chilean samples, probably reflecting its more marked geographic isolation compared to the other regions. Multidimensional scaling (MDS) analysis based on RST genetic distances suggested a close proximity of Chilean Y-chromosome profiles to European ones. Consistently, haplogroups inferred from Y-STR profiles revealed that the Native American component constituted only 8% of all the haplotypes, and this component ranged from 5% in the Centre of the country to 9-10% in the South and 13% in the North, which is in good agreement with the distribution of Native American communities in these regions. AMOVA computed on inferred haplogroups confirmed the very low among variation observed in Chilean populations. The present project provides the first Chilean dataset to the international Y-chromosome STR Haplotype Reference Database (YHRD) and it is also the first reference database for Y-chromosome forensic casework of the country.


Subject(s)
Chromosomes, Human, Y , Microsatellite Repeats , White People/genetics , Chile , Databases, Genetic , Europe/ethnology , Forensic Genetics/methods , Genetics, Population/methods , Haplotypes , Humans , Male , Racial Groups , Urban Population
11.
Forensic Sci Int Genet ; 20: 81-88, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26517175

ABSTRACT

The territory of Chile is particularly long and narrow, which combined with its mountainous terrain, makes it a unique scenario for human genetic studies. We obtained 995 control region mitochondrial DNA (mtDNA) sequences from Chileans representing populations living at different latitudes of the country from the North to the southernmost region. The majority of the mtDNA profiles are of Native American origin (∼88%). The remaining haplotypes are mostly of recent European origin (∼11%), and only a minor proportion is of recent African ancestry (∼1%). While these proportions are relatively uniform across the country, more structured patterns of diversity emerge when examining the variation from a phylogeographic perspective. For instance, haplogroup A2 reaches ∼9% in the North, and its frequency decreases gradually to ∼1% in the southernmost populations, while the frequency of haplogroup D (sub-haplogroups D1 and D4) follows the opposite pattern: 36% in the southernmost region, gradually decreasing to 21% in the North. Furthermore, there are remarkable signatures of founder effects in specific sub-clades of Native American (e.g. haplogroups D1j and D4p) and European (e.g. haplogroups T2b3 and K1a4a1a+195) ancestry. We conclude that the magnitude of the latitudinal differences observed in the patterns of mtDNA variation might be relevant in forensic casework.


Subject(s)
DNA, Mitochondrial/genetics , Chile , DNA, Mitochondrial/analysis , Ethnicity/genetics , Founder Effect , Genetic Variation , Genetics, Population , Haplotypes , Humans , Male , Microsatellite Repeats , Phylogeny , Phylogeography , Sequence Analysis, DNA
12.
J Mol Microbiol Biotechnol ; 25(2-3): 195-208, 2015.
Article in English | MEDLINE | ID: mdl-26159079

ABSTRACT

Laboratory and industrial cultures of Escherichia coli employ media containing glucose which is mainly transported and phosphorylated by the phosphotransferase system (PTS). In these strains, 50% of the phosphoenolpyruvate (PEP), which results from the catabolism of transported glucose, is used as a phosphate donor for its phosphorylation and translocation by the PTS. This characteristic of the PTS limits the production of industrial biocommodities that have PEP as a precursor. Furthermore, when E. coli is exposed to carbohydrate mixtures, the PTS prevents expression of catabolic and non-PTS transport genes by carbon catabolite repression and inducer exclusion. In this contribution, we discuss the main strategies developed to overcome these potentially limiting effects in production strains. These strategies include adaptive laboratory evolution selection of PTS(-) Glc(+) mutants, followed by the generation of strains that recover their ability to grow with glucose as a carbon source while allowing the simultaneous consumption of more than one carbon source. We discuss the benefits of using alternative glucose transport systems and describe the application of these strategies to E. coli strains with specific genetic modifications in target pathways. These efforts have resulted in significant improvements in the production of diverse biocommodities, including aromatic metabolites, biofuels and organic acids.


Subject(s)
Escherichia coli Proteins/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Metabolic Engineering , Phosphoenolpyruvate Sugar Phosphotransferase System/genetics , Biofuels , Biological Transport , Catabolite Repression , Directed Molecular Evolution , Escherichia coli/growth & development , Escherichia coli Proteins/metabolism , Glucose/metabolism , Phenotype , Phosphoenolpyruvate/metabolism , Phosphoenolpyruvate Sugar Phosphotransferase System/metabolism , Phosphorylation
13.
Forensic Sci Int Genet ; 19: 35-36, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26074412

ABSTRACT

We estimated the allele frequencies for the 15 autosomal STR loci included in the AmpFlSTR(®) Identifiler (Applied Biosystems, USA) in a sample of 986 unrelated non-Native American individuals collected at five different localities from Chile, namely, Iquique, Santiago, Concepción, Temuco and Punta Arenas. Frequency distributions and several forensic parameters were estimated at each recruitment site. In addition, analyses were carried out merging the data into five sample locations. No significant statistical differences could be detected between different regions in Chile. These data represent one of the very few studies performed on autosomal STRs in Chile and therefore provide a useful tool for forensic casework carried out in the country.


Subject(s)
Databases, Genetic , Microsatellite Repeats/genetics , Chile , Gene Frequency , Humans
14.
Food Sci Technol Int ; 20(6): 405-19, 2014 Sep.
Article in English | MEDLINE | ID: mdl-23785068

ABSTRACT

The retention of solutes in the ice formed in a falling-film freeze concentrator (multi-plate freeze-concentrator) was analysed. Solutions of fructose, glucose and sucrose and a simulated juice with initial concentrations of 5, 10, 15 and 20 °Brix were freeze concentrated. The ice produced in the four steps of the process retains solutes at levels of 1.0-8.8 °Brix (expressed as solute mass fraction in the ice). The recovery of these solutes during thawing can increase overall system efficiency. All thawing steps were carried out dividing the sample in 10 fractions at 20 ℃. The first thawed fractions showed solute concentrations that were 1.9-3.3 times higher than the mean solute mass fraction in the ice, while the last fractions of ice showed very low levels of retained solutes, less than 0.2 times the mean solute mass fraction in the ice. It was found that fractionated thawing can recover most of the solute content in the ice. The procedure presented in the present study allows the determination of the solute concentration achieved in the various thawing fractions and predicts the thawing time required for a given form factor, melting temperature and initial solute mass fraction in the ice.


Subject(s)
Freezing , Fruit and Vegetable Juices , Ice , Monosaccharides , Solutions/chemistry , Sucrose , Temperature , Food Technology , Fructose , Glucose
15.
Cir. Esp. (Ed. impr.) ; 91(4): 237-242, abr. 2013. ilus
Article in Spanish | IBECS | ID: ibc-111382

ABSTRACT

Introducción La fístula quilosa es poco frecuente en el postoperatorio de diferentes tipos de intervenciones abdominales, especialmente del espacio retroperitoneal, como las pancreáticas. Puede desarrollarse también en el curso de una pancreatitis aguda grave. El tratamiento inicialmente es conservador y puede dilatarse en el tiempo, aunque puede abreviarse con el uso de somatostatina u octreótido. Pacientes y métodos Los pacientes afectos de enfermedad pancreática que presentaron una fístula quilosa durante su ingreso (débito mayor de 100 cc/24h, niveles de amilasa pancreática normales y triglicéridos superiores a 110mg/dl) fueron tratados inicialmente con dieta absoluta y nutrición parenteral total, seguido de la administración de octreótido 0,1mg/8h por vía subcutánea. Resultados Cuatro pacientes mujeres de entre 55 y 80 años, presentando cirugía pancreática o pancreatitis aguda, desarrollaron una fístula quilosa con débitos entre 100 y 2.000ml cada 24h. Tras la administración de octreótido, las fístulas se solucionaron entre el quinto y el séptimo día de tratamiento, sin presentar recidiva durante un seguimiento de 2 a 4 años. Conclusiones Dado que el tratamiento médico de la fístula quilosa en general se asocia a un curso lento, y que la administración de somatostatina u octreótido produce una drástica resolución del cuadro, tal como hemos constatado en nuestra observación y como aparece descrito por otros autores, el inicio precoz de este tratamiento puede acelerar su curación, lo que redunda en un acortamiento de la recuperación del paciente y en una disminución del gasto hospitalario (AU)


Introduction: A chyle fistula is an uncommon complication following abdominal and pancreatic surgery, particularly in the retroperitoneal compartment. It can also appear as a complication of a severe acute pancreatitis. Medical treatment is the initial approach, but resolution is often (..) (AU)


Subject(s)
Humans , Female , Middle Aged , Aged , Aged, 80 and over , Octreotide/pharmacokinetics , Intestinal Fistula/drug therapy , Pancreatitis/surgery , Pancreatectomy/adverse effects , Treatment Outcome , Postoperative Complications , Chylous Ascites/etiology , Retrospective Studies
16.
Cir Esp ; 91(4): 237-42, 2013 Apr.
Article in Spanish | MEDLINE | ID: mdl-23228417

ABSTRACT

INTRODUCTION: A chyle fistula is an uncommon complication following abdominal and pancreatic surgery, particularly in the retroperitoneal compartment. It can also appear as a complication of a severe acute pancreatitis. Medical treatment is the initial approach, but resolution is often slow. Somatostatin or octreotide can help in accelerating the resolution of fistulae. PATIENTS AND METHODS: Patients developing a chyle fistula (output > 100ml/24h, normal amylase levels and triglyceride concentrations above 110mg/dl) associated with pancreatic disorders were treated with oral intake restriction and parenteral nutrition, followed by subcutaneous octreotide 0.1mg/8h. RESULTS: Four female patients from 55 to 80 years old, underwent pancreatic surgery or presented with an acute pancreatitis, were treated. Chyle fistulae ranging from 100 to 2,000ml/24h were treated with octreotide, being resolved within five to seven days. No recurrence has been found in a 2 to 4 years follow up. CONCLUSIONS: We have found that chyle fistula medical treatment is often related to a slow resolution, somatostatin or octreotide administration dramatically reduces its duration. Other previously reported studies have also shown that the quick onset of such treatment can accelerate the whole process, leading to a shorter recovery and lower hospital costs.


Subject(s)
Chyle , Gastrointestinal Agents/therapeutic use , Octreotide/therapeutic use , Pancreatic Fistula/drug therapy , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Pancreatic Fistula/complications , Pancreatitis/complications , Postoperative Complications/drug therapy
17.
PLoS Genet ; 8(3): e1002554, 2012.
Article in English | MEDLINE | ID: mdl-22412386

ABSTRACT

Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R² > 0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region.


Subject(s)
American Indian or Alaska Native/genetics , Black People/genetics , Genetic Markers , Population Dynamics , White People/genetics , Genome, Human , Humans , Latin America
18.
Acta méd. colomb ; 36(2): 93-97, abr.-jun. 2011. ilus
Article in Spanish | LILACS | ID: lil-635343

ABSTRACT

Presentamos el caso de una paciente de 28 años quien consulta a nuestra clínica por pérdida bilateral y crónica de la visión y episodios de síncope de reciente aparición. No tenía historia de síntomas sistémicos o debidos a disminución del flujo sanguíneo en las extremidades. Durante la hospitalización se encuentra déficit de pulso en las extremidades superiores. La arteriografía muestra estenosis severa de ambas arterias subclavias, carótidas comunes y la arteria vertebral derecha. Se hizo un diagnóstico de arteritis de Takayasu. Se presenta una revisión corta de la patología (Acta Med Colomb 2011; 36: 93-97).


We describe the case of a 28-year-old woman who presented to our clinic with a history of chronic bilateral visual loss and recent episodes of syncope. She did not have a history of systemic symptoms or manifestations of reduced blood flow in her limbs. During her hospital stay, deficient pulses were discovered in both arms. Once hospitalized the physician discloses a pulse deficit in both arms. Angiographic studies showed severe bilateral stenosis of the subclavian and carotid arteries and of the right vertebral artery. The diagnosis of Takayasu's arteritis was confirmed. A brief review of this disease is presented in this paper (Acta Med Colomb 2011; 36: 93-97).

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