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1.
Nat Plants ; 8(5): 491-499, 2022 05.
Article in English | MEDLINE | ID: mdl-35534721

ABSTRACT

Crop landraces have unique local agroecological and societal functions and offer important genetic resources for plant breeding. Recognition of the value of landrace diversity and concern about its erosion on farms have led to sustained efforts to establish ex situ collections worldwide. The degree to which these efforts have succeeded in conserving landraces has not been comprehensively assessed. Here we modelled the potential distributions of eco-geographically distinguishable groups of landraces of 25 cereal, pulse and starchy root/tuber/fruit crops within their geographic regions of diversity. We then analysed the extent to which these landrace groups are represented in genebank collections, using geographic and ecological coverage metrics as a proxy for genetic diversity. We find that ex situ conservation of landrace groups is currently moderately comprehensive on average, with substantial variation among crops; a mean of 63% ± 12.6% of distributions is currently represented in genebanks. Breadfruit, bananas and plantains, lentils, common beans, chickpeas, barley and bread wheat landrace groups are among the most fully represented, whereas the largest conservation gaps persist for pearl millet, yams, finger millet, groundnut, potatoes and peas. Geographic regions prioritized for further collection of landrace groups for ex situ conservation include South Asia, the Mediterranean and West Asia, Mesoamerica, sub-Saharan Africa, the Andean mountains of South America and Central to East Asia. With further progress to fill these gaps, a high degree of representation of landrace group diversity in genebanks is feasible globally, thus fulfilling international targets for their ex situ conservation.


Subject(s)
Crops, Agricultural , Plant Breeding , Crops, Agricultural/genetics , Asia, Eastern , South America , Triticum/genetics
2.
Blood Purif ; 50(1): 110-118, 2021.
Article in English | MEDLINE | ID: mdl-33176299

ABSTRACT

INTRODUCTION: A new generation of hemodialysis (HD) membranes called medium cut-off (MCO) membranes possesses enhanced capacities for middle molecule clearance, which have been associated with adverse outcomes in this population. These improvements could potentially positively impact patient-reported outcomes (PROs). OBJECTIVE: The objective of this study was to evaluate the impact of MCO membranes on PROs in a cohort of HD patients in Colombia. METHODS: This was a prospective, multicenter, observational cohort study of 992 patients from 12 renal clinics in Colombia who were switched from high-flux HD to MCO therapy and observed for 12 months. Changes in Kidney Disease Quality of Life 36-Item Short Form Survey (KDQoL-SF36) domains, Dialysis Symptom Index (DSI), and restless legs syndrome (RLS) 12 months after switching to MCO membranes were compared with time on high-flux membranes. Repeated measures of ANOVA were used to evaluate changes in KDQoL-SF36 scores; severity scoring was used to assess DSI changes over time; Cochran's Q test was used to evaluate changes in frequency of diagnostic criteria of RLS. RESULTS: During 12 months of follow-up, 3 of 5 KDQoL-SF36 domains improved compared with baseline: symptoms (p < 0.0001), effects of kidney disease (p < 0.0001), and burden of kidney disease (p < 0.001). The proportion of patients diagnosed with RLS significantly decreased from 22.1% at baseline to 10% at 12 months (p < 0.0001). No significant differences in the number of symptoms (DSI, p = 0.1) were observed, although their severity decreased (p = 0.009). CONCLUSIONS: In conventional HD patients, the expanded clearance of large middle molecules with MCO-HD membranes was associated with higher health-related quality of life scores and a decrease in the prevalence of RLS.


Subject(s)
Kidney Failure, Chronic/therapy , Membranes, Artificial , Patient Reported Outcome Measures , Quality of Life , Registries , Renal Dialysis/instrumentation , Aged , Colombia/epidemiology , Female , Follow-Up Studies , Humans , Kidney Failure, Chronic/epidemiology , Male , Middle Aged , Prospective Studies , Renal Dialysis/adverse effects , Restless Legs Syndrome/epidemiology , Restless Legs Syndrome/etiology
3.
Sensors (Basel) ; 20(11)2020 Jun 02.
Article in English | MEDLINE | ID: mdl-32498271

ABSTRACT

The electrocardiogram records the heart's electrical activity and generates a significant amount of data. The analysis of these data helps us to detect diseases and disorders via heart bio-signal abnormality classification. In unbalanced-data contexts, where the classes are not equally represented, the optimization and configuration of the classification models are highly complex, reflecting on the use of computational resources. Moreover, the performance of electrocardiogram classification depends on the approach and parameter estimation to generate the model with high accuracy, sensitivity, and precision. Previous works have proposed hybrid approaches and only a few implemented parameter optimization. Instead, they generally applied an empirical tuning of parameters at a data level or an algorithm level. Hence, a scheme, including metrics of sensitivity in a higher precision and accuracy scale, deserves special attention. In this article, a metaheuristic optimization approach for parameter estimations in arrhythmia classification from unbalanced data is presented. We selected an unbalanced subset of those databases to classify eight types of arrhythmia. It is important to highlight that we combined undersampling based on the clustering method (data level) and feature selection method (algorithmic level) to tackle the unbalanced class problem. To explore parameter estimation and improve the classification for our model, we compared two metaheuristic approaches based on differential evolution and particle swarm optimization. The final results showed an accuracy of 99.95%, a F1 score of 99.88%, a sensitivity of 99.87%, a precision of 99.89%, and a specificity of 99.99%, which are high, even in the presence of unbalanced data.


Subject(s)
Arrhythmias, Cardiac , Electrocardiography , Signal Processing, Computer-Assisted , Algorithms , Arrhythmias, Cardiac/classification , Arrhythmias, Cardiac/diagnosis , Cluster Analysis , Databases, Factual , Humans
4.
Toxins (Basel) ; 10(2)2018 02 17.
Article in English | MEDLINE | ID: mdl-29462980

ABSTRACT

The Colombian rattlesnake Crotalus durissus cumanensis is distributed in three geographic zones of the country: the Atlantic Coast, the upper valley of the Magdalena River, and the eastern plains of the Colombian Orinoquía. Its venom induces neurological symptoms, such as eyelid ptosis, myasthenic facies, and paralysis of the respiratory muscles, which can lead to death. Identification and analysis of C. d. cumanensis showed nine groups of proteins responsible for the neurotoxic effect, of which the crotoxin complex was the most abundant (64.71%). Immunorecognition tests of C. d. cumanensis showed that the use of a commercial antivenom manufactured in Mexico resulted in immunoreactivity.


Subject(s)
Crotalid Venoms/chemistry , Crotalus , Reptilian Proteins/analysis , Animals , Antivenins/immunology , Colombia , Crotalid Venoms/immunology , Proteomics
5.
Vitae (Medellín) ; 21(1): 38-48, 2014. Ilus
Article in English | LILACS, COLNAL | ID: biblio-986734

ABSTRACT

Antecedentes: las mordeduras de serpientes representan un problema de salud pública relevante en muchas regiones del mundo, particularmente en los países tropicales y subtropicales de África, Asia, América Latina y Oceanía. Los venenos de serpientes son mezclas complejas de enzimas y proteínas tóxicas, donde los componentes más importantes y abundantes que dañan los músculos en los venenos de serpientes son las fosfolipasas A2 (PLA2). Objetivo: Aislar y caracterizar una fosfolipasa A2 del veneno de Venezuela Bothrops para obtener información sobre la composición del veneno de esta especie. Materiales y métodos: La cromatografía de intercambio catiónico seguida de HPLC de fase inversa se usó para purificar la proteína. La espectrometría de masas se utilizó para determinar su masa molecular. La caracterización bioquímica se realizó utilizando un sustrato sintético (ácido 4-nitro-3-octanoiloxi-benzoico). La actividad miotóxica y de inducción de edema de la toxina se probó en ratones, midiendo la actividad de la creatina quinasa plasmática y el diámetro de la almohadilla de la pata, respectivamente. Además, se examinó la actividad citotóxica de mioblastos y miotubos C2C12 del músculo esquelético murino. Resultados: se purificó una PLA2 de Bothrops asper veneno de Colombia (BaspCol-PLA2). Su masa molecular fue de 13974.6 Da. La enzima hidrolizó un sustrato sintético con un KM de 3.11 mM y un VMax de 4.47 nmol / min, mostrando una actividad máxima a 40 ° C y a pH 8.0. La PLA2 requería Ca2 + para la actividad. La adición de Mg2 +, Cd2 +, Mn2 + y Zn2 + (10 mM) en presencia de baja concentración de Ca2 + (1 mM) disminuyó la actividad de la enzima. La sustitución de Ca2 + por los cationes divalentes mencionados también redujo la actividad a niveles similares a los de la ausencia de Ca2 +. Tres fragmentos internos (CCFVHDCCYGK, AAAI / LCFRDNI / LNTYNDKK, DAAI / LCFR) identificada mediante un análisis de espectrometría de masas mostró similitud con las PLA2 de B. asper informadas previamente. En ratones, BaspCol-PLA2 indujo un notable efecto miotóxico local y un edema moderado en la almohadilla del pie. In vitro, esta enzima indujo un efecto citotóxico tanto en los mioblastos como en los miotubos. Además, se clasificó como PLA2 débilmente anticoagulante, mostrando este efecto en concentraciones entre 3 y 10 µg / mL cuando se usa plasma humano. Conclusiones: Una PLA2 se purificó y se llamó BaspCol-PLA2, esta enzima mostró actividad catalítica y una masa molecular de 13974.6 Da. La toxina mostró actividades miotóxicas, formadoras de edema, anticoagulantes y citotóxicas. BaspCol-PLA2 indujo un notable efecto miotóxico local y un edema moderado en la almohadilla del pie. In vitro, esta enzima indujo un efecto citotóxico tanto en los mioblastos como en los miotubos. Además, se clasificó como PLA2 débilmente anticoagulante, mostrando este efecto en concentraciones entre 3 y 10 µg / mL cuando se usa plasma humano. Conclusiones: Una PLA2 se purificó y se llamó BaspCol-PLA2, esta enzima mostró actividad catalítica y una masa molecular de 13974.6 Da. La toxina mostró actividades miotóxicas, formadoras de edema, anticoagulantes y citotóxicas. BaspCol-PLA2 indujo un notable efecto miotóxico local y un edema moderado en la almohadilla del pie. In vitro, esta enzima indujo un efecto citotóxico tanto en los mioblastos como en los miotubos. Además, se clasificó como PLA2 débilmente anticoagulante, mostrando este efecto en concentraciones entre 3 y 10 µg / mL cuando se usa plasma humano. Conclusiones: Una PLA2 se purificó y se llamó BaspCol-PLA2, esta enzima mostró actividad catalítica y una masa molecular de 13974.6 Da. La toxina mostró actividades miotóxicas, formadoras de edema, anticoagulantes y citotóxicas. esta enzima mostró actividad catalítica y masa molecular de 13974.6 Da. La toxina mostró actividades miotóxicas, formadoras de edema, anticoagulantes y citotóxicas. esta enzima mostró actividad catalítica y masa molecular de 13974.6 Da. La toxina mostró actividades miotóxicas, formadoras de edema, anticoagulantes y citotóxicas.


Subject(s)
Humans , Phospholipases A2 , Poisons , Snakes , Chromatography
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