Análisis de concordancia de diferentes metodologías para la identificación de aislamientos orales de especies de candida

Background: The yeasts species determination is fundamental not only for an accurate diagnosis but also for establishing a suitable patient treatment. We performed a concordance study of five methodologies for the species identification of oral isolates of Candida in Colombia. Methods: Sixty-seven Candida isolates were tested by; API® 20C-AUX, Vitek®2 Compact, Vitek®MS, Microflex® and a molecular test (panfungal PCR and sequencing). The commercial cost and processing time of the samples was done by graphical analysis. Results: Panfungal PCR differentiated 12 species of Candida, Vitek®MS and Microflex® methods identified 9 species, and API® 20C-AUX and Vitek®2 Compact methods identified 8 species each. Weighted Kappa (wK) showed a high agreement between Panfungal PCR, Vitek®MS, Microflex® and API® 20C-AUX (wK 0.62-0.93). The wK that involved the Vitek®2 Compact method presented moderate or good concordances compared with the other methods (wK 0.56-0.73). Methodologies based on MALDI TOF MS required 4 minutes to generate results and the Microflex® method had the lowest selling price. Conclusion: The methods evaluated showed high concordance in their results, being higher for the molecular methods and the methodologies based on MALDI TOF. The latter are faster and cheaper, presenting as promising alternatives for the routine identification of yeast species of the genus Candida. © 2018. Universidad del Valle

Análisis de concordancia de diferentes metodologías para la identificación de aislamientos orales de especies de candida

Background: The yeasts species determination is fundamental not only for an accurate diagnosis but also for establishing a suitable patient treatment. We performed a concordance study of five methodologies for the species identification of oral isolates of Candida in Colombia. Methods: Sixty-seven Candida isolates were tested by; API® 20C-AUX, Vitek®2 Compact, Vitek®MS, Microflex® and a molecular test (panfungal PCR and sequencing). The commercial cost and processing time of the samples was done by graphical analysis. Results: Panfungal PCR differentiated 12 species of Candida, Vitek®MS and Microflex® methods identified 9 species, and API® 20C-AUX and Vitek®2 Compact methods identified 8 species each. Weighted Kappa (wK) showed a high agreement between Panfungal PCR, Vitek®MS, Microflex® and API® 20C-AUX (wK 0.62-0.93). The wK that involved the Vitek®2 Compact method presented moderate or good concordances compared with the other methods (wK 0.56-0.73). Methodologies based on MALDI TOF MS required 4 minutes to generate results and the Microflex® method had the lowest selling price. Conclusion: The methods evaluated showed high concordance in their results, being higher for the molecular methods and the methodologies based on MALDI TOF. The latter are faster and cheaper, presenting as promising alternatives for the routine identification of yeast species of the genus Candida. © 2018. Universidad del Valle

Environmental influence on the worldwide prevalence of a 776C→G variant in the transcobalamin gene (TCN2)

Background: A 776C→G variant (dbSNP ID: rs1801198) in the transcobalamin gene (TCN2; MIM# 275350) decreases the cellular and plasma concentration of transcobalamin and thereby influences the cellular availability of vitamin B12. Objective: To evaluate the worldwide prevalence of this variant and its association with homocysteine plasma level. Methods: The study was performed in 1433 apparently healthy subjects, including Afro-Americans and Afro-Africans and in 251 Afro-Africans participants with severe malaria. Results: The frequencies of the 776G allele were the highest in China (0.607; 95% Cl 0.554 to 0.659), low in West Africa (Bénin and Togo, 0.178; 0.154 to 0.206), and intermediate in France (0.445; 0.408 to 0.481), Italy (0.352; 0.299 to 0.409), Morocco (0.370; 0.300 to 0.447) and Mexico (0.374; 0.392 to 0.419). The 776G genotype was more frequent in Afro-Americans from New York (16.7; 8.4 to 30.7) and in Afro-African patients with severe malaria (6.0%; 95% Cl 3.7 to 9.6) than in healthy Afro-African volunteers (p= 0.0004 and p= 0.033, respectively), while no difference was observed for MTHFR 677TT and 677T alleles. A disequilibrium of TCN2 genotype distribution was recorded in patients with severe malaria, with a twofold higher GG genotype than expected (p=0.010). An association between the TCN2 polymorphism and homocysteine was observed only in Mexico and France, the two countries with the highest rate of low plasma concentration of vitamin B12 (<100 p

Heterogenous Distribution of <i>MTHFR</i> Gene Variants among Mestizos and Diverse Amerindian Groups from Mexico

<div><p>Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in folate metabolism. Folate deficiency has been related to several conditions, including neural tube defects (NTDs) and cardiovascular diseases. Hence, <i>MTHFR</i> genetic variants have been studied worldwide, particularly the C677T and A1298C. We genotyped the C677T and A1298C <i>MTHFR</i> polymorphisms in Mexican Amerindians (MAs), from the largest sample included in a genetic study (n = 2026, from 62 ethnic groups), and in a geographically-matched Mexican Mestizo population (MEZ, n = 638). The 677T allele was most frequent in Mexican individuals, particularly in MAs. The frequency of this allele in both MAs and MEZs was clearly enriched in the South region of the country, followed by the Central East and South East regions. In contrast, the frequency of the 1298C risk allele in Mexicans was one of the lowest in the world. Both in MAs and MEZs the variants 677T and 1298C displayed opposite allele frequency gradients from southern to northern Mexico. Our findings suggest that in Mestizos the 677T allele was derived from Amerindians while the 1298C allele was a European contribution. Some subgroups showed an allele frequency distribution that highlighted their genetic diversity. Notably, the distribution of the frequency of the 677T allele was consistent with that of the high incidence of NTDs reported in MEZ.</p></div

Geographic distribution of allele frequencies for the C677T polymorphism in the MA population.

<p>CDMX, Mexico City; MEX, Mexico State; MOR, Morelos; OAX, Oaxaca; PUE, Puebla; SLP, San Luis Potosí. Striped States were not sampled because they are inhabited by neighboring indigenous included in this study. *States without indigenous population [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163248#pone.0163248.ref032" target="_blank">32</a>].</p

70º Aniversario de la declaración universal de derechos humanos. La protección internacional de los Derechos Humanos en cuestión

Segundo volúmen de la Colección Perspectivas Iberoamericanas sobre la justicia. La Declaración Universal de los Derechos Humanos de las Naciones Unidas cumple, el 10 de diciembre de 2018, setenta años. La simbólica fecha obliga a los investigadores en derechos humanos a reflexionar críticamente sobre los avances y límites de un complejo sistema de normas y, sobre todo, de valores culturales sustentados en la matriz liberal occidental. Desde entonces, ha habido indiscutibles avances institucionales y normativos, como la creación del Consejo de Derechos Humanos, varios pactos y declaraciones complementarias, órganos específicos, tribunales internacionales, jurisprudencia, constituciones estatales, una infinidad de instituciones basadas en esta “ética mínima universal” que, contradictoriamente, no logró evitar un conjunto de catástrofes humanitarias y de vulneración de derechos. La primera década del siglo XX trae un reflejo limitante al consenso de la posguerra, pues la agresividad de los Estados hegemónicos, en alianza con intereses privados transnacionales, pone en jaque la capacidad del sistema protector frente a guerras humanitarias e internacionales. tratados económicos de nueva generación aquellos que excluyen por completo a la democracia del proceso de negociación.A Declaração Universal dos Direitos Humanos das Nações Unidas completa, em 10 de diciembre de 2018, setenta años. A data simbólica exige dos pesquisadores em direitos humanos uma reflexão crítica a respeito dos avanços y dos limites de um sistema complexo de normas e, principalmente, de valores culturales apoiados na matriz liberal ocidental. De lá para cá, houve indiscutível avanço institucional e normativo, do qual é exemplo a criação do Conselho de Direitos Humanos, diversos pactos e declarações complementarios, órgão específicos, tribunais internacionais, jurisprudência, constituições dos States, uma infinidade de instituições pautadas nesse “mínimo ético universal” que, contraditoriamente, não conseguiu evitar um conjunto de catástrofes humanitárias e de violação de direitos. A primeira década do século XX traz uma reflexão limite para o consenso do pós-guerra, pois a agressividade dos States hegemônicos, em aliança com interesses private transnacionais, põe em check a capacidade do sistema protectivo diante das guerras humanitárias e dos tratados internacionais econômicos de nueva generación aqueles que excluem completamente a democracia do processo negociador