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1.
Cureus ; 16(4): e57544, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38707016

ABSTRACT

Heart failure (HF) patients frequently present with comorbidities such as atrial fibrillation (AF) or other cardiovascular conditions, elevating their risk of thromboembolic events. Consequently, anticoagulation therapy is often considered for thromboprophylaxis, although its initiation in HF patients is complicated by concomitant bleeding risk factors. This review explores the paradoxical relationship between HF, increased bleeding risk, and the potential benefits of anticoagulation. Through an examination of existing evidence from clinical trials, observational studies, and meta-analyses, we aim to elucidate the role of anticoagulation in HF patients with increased bleeding risk. Despite guidelines recommending anticoagulation for certain HF patients with AF or other thromboembolic risk factors, uncertainty persists regarding the optimal management strategy for those at heightened risk of bleeding. The review discusses the pathophysiological mechanisms linking HF and thrombosis, challenges in bleeding risk assessment, and strategies to minimize bleeding risk while optimizing thromboprophylaxis. Shared decision-making between clinicians and patients is emphasized as essential for individualized treatment plans that balance the potential benefits of anticoagulation against the risk of bleeding complications. Furthermore, it examines emerging anticoagulant agents and their potential role in HF management, highlighting the need for further research to delineate optimal management strategies and inform evidence-based practice. In conclusion, while anticoagulation holds promise for improving outcomes in HF patients, careful consideration of patient-specific factors and ongoing research efforts are essential to optimize therapeutic strategies in this population.

2.
Cienc. act. fis. (Talca, En linea) ; 23(2): 1-15, dez. 2022. ilus, graf, tab
Article in Spanish | LILACS | ID: biblio-1421092

ABSTRACT

La antropometría, potencia, velocidad y agilidad son factores relacionados con el rendimiento en el fútbol. Sin embargo, la relación entre las medidas antropométricas y las capacidades físicas se pueden evaluar. El objetivo del estudio fue estimar la correlación entre antropometría, potencia, velocidad y agilidad. Participaron 17 futbolistas semiprofesionales categoría sub 15, (peso corporal: 60,64 ± 5.78 kg; estatura: 1,72 ± 0,06 m; edad: 15,53 ± 0,50 años). Se correlacionó la antropometría y agilidad con el salto vertical, asimismo, la agilidad con la velocidad mediante Coeficiente de correlación de Pearson, p = 0,05. Los resultados indican que no existe significancia entre perímetro del muslo (r = 0,16; p = 0,24), peso corporal (r = 0,30; p = 0,15), estatura, (r = 0,36; p = 0,51), largo de extremidad inferior (r = 0,34; p = 0,17), salto vertical-agilidad (r = 0,16; p = 0,52), velocidad en línea recta 20m-agilidad (r = 0,25; p = 0,33). Se concluye que no existe significancia entre las variables de antropometría, potencia, velocidad y agilidad en los futbolistas semiprofesionales categoría sub 15 del equipo de la liga profesional de la primera división de Venezuela, estudiantes de Mérida Fútbol Club.


Anthropometry, power, speed, and agility are factors related to performance in soccer. However, the relationship between anthropometric measurements and physical abilities can be evaluated. The objective of this study was to estimate the correlation between anthropometry, power, speed, and agility. Seventeen semi-professional U15 category soccer players participated (body weight: 60.64 ± 5.78 kg, height: 1.72 ± 0.06 m, age: 15.53 ± 0.50 years). Anthropometry and agility were correlated with vertical jump; agility was also correlated with speed by Pearson, p = 0.05. The results indicate that there is no significance between thigh circumference (r= 0.16; p= 0.24), body weight (r= 0.30; p= 0.15), height (r= 0.36; p= 0.51), lower extremity length (r= 0.34; p= 0.17), vertical jump-agility (r= 0.16; p= 0.52), and straight-line speed 20m-agility (r= 0.25; p= 0.33). It is concluded that there is no significance between the variables of anthropometry, power, speed, and agility in semi-professional soccer players in the under 15 category from the professional league of the first division of Venezuela; students from the Mérida Soccer Club.


Antropometria, potência, velocidade e agilidade são factores relacionados com o desempenho no futebol. Contudo, a relação entre as medidas antropométricas e as capacidades físicas pode ser avaliada. O objectivo era estimar a correlação entre antropometria, potência, velocidade e agilidade. Participaram dezassete jogadores de futebol semi-profissionais, categoria sub-15 (peso corporal. 60,64 ± 5,78 kg, altura 1,72 ± 0,06 m, idade 15,53 ± 0,50 anos). A antropometria e a agilidade foram correlacionadas com o salto vertical, e a agilidade foi correlacionada com a velocidade por Pearson, p = 0,05. Os resultados indicam que não há significado entre a circunferência da coxa (r= 0,16; p= 0,24), peso corporal (r= 0,30; p= 0,15), altura, (r= 0,36; p= 0,51), comprimento dos membros inferiores (r= 0,34; p= 0,17), agilidade de salto vertical (r= 0,16; p= 0,52), velocidade de linha recta 20m-agilidade (r= 0,25; p= 0,33). Conclui-se que não há significado entre as variáveis de antropometria, potência, velocidade e agilidade nos jogadores de futebol semi-profissionais com menos de 15 categorias da equipa da liga profissional da primeira divisão da Venezuela, estudantes do clube de futebol de Mérida.


Subject(s)
Humans , Male , Adolescent , Exercise , Anthropometry , Physical Fitness , Venezuela , Body Height , Body Weight
3.
Front Genet ; 12: 690366, 2021.
Article in English | MEDLINE | ID: mdl-34650589

ABSTRACT

Currently, the vast majority of genomic research cohorts are made up of participants with European ancestry. Genomic medicine will only reach its full potential when genomic studies become more broadly representative of global populations. We are working to support the establishment of genomic medicine in developing countries in Latin America via studies of ethnically and ancestrally diverse Colombian populations. The goal of this study was to analyze the effect of ethnicity and genetic ancestry on observed disease prevalence and predicted disease risk in Colombia. Population distributions of Colombia's three major ethnic groups - Mestizo, Afro-Colombian, and Indigenous - were compared to disease prevalence and socioeconomic indicators. Indigenous and Mestizo ethnicity show the highest correlations with disease prevalence, whereas the effect of Afro-Colombian ethnicity is substantially lower. Mestizo ethnicity is mostly negatively correlated with six high-impact health conditions and positively correlated with seven of eight common cancers; Indigenous ethnicity shows the opposite effect. Malaria prevalence in particular is strongly correlated with ethnicity. Disease prevalence co-varies across geographic regions, consistent with the regional distribution of ethnic groups. Ethnicity is also correlated with regional variation in human development, partially explaining the observed differences in disease prevalence. Patterns of genetic ancestry and admixture for a cohort of 624 individuals from Medellín were compared to disease risk inferred via polygenic risk scores (PRS). African genetic ancestry is most strongly correlated with predicted disease risk, whereas European and Native American ancestry show weaker effects. African ancestry is mostly positively correlated with disease risk, and European ancestry is mostly negatively correlated. The relationships between ethnicity and disease prevalence do not show an overall correspondence with the relationships between ancestry and disease risk. We discuss possible reasons for the divergent health effects of ethnicity and ancestry as well as the implication of our results for the development of precision medicine in Colombia.

4.
Sci Rep ; 11(1): 19822, 2021 Oct 06.
Article in English | MEDLINE | ID: mdl-34615892

ABSTRACT

Surface albedo is an important forcing parameter that drives the radiative energy budget as it determines the fraction of the downwelling solar irradiance that the surface reflects. Here we report on ground-based measurements of the spectral albedo (350-2200 nm) carried out at 20 sites across a North-South transect of approximately 1300 km in the Atacama Desert, from latitude 18° S to latitude 30° S. These spectral measurements were used to evaluate remote sensing estimates of the albedo derived from the Moderate Resolution Imaging Spectroradiometer (MODIS). We found that the relative mean bias error (RMBE) of MODIS-derived estimates was within ± 5% of ground-based measurements in most of the Atacama Desert (18-27° S). Although the correlation between MODIS-derived estimates and ground-based measurements remained relatively high (R= 0.94), RMBE values were slightly larger in the southernmost part of the desert (27-30° S). Both MODIS-derived data and ground-based measurements show that the albedo at some bright spots in the Atacama Desert may be high enough (up to 0.25 in visible range) for considerably boosting the performance of bifacial photovoltaic technologies (6-12%).

5.
J Cataract Refract Surg ; 47(4): 445-449, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-33196573

ABSTRACT

PURPOSE: To evaluate the safety and efficacy of 80-µm flap femtosecond laser-assisted LASIK and the early clinical and refractive outcomes in the correction of myopia and myopic astigmatism. SETTING: Private practice, outpatient. DESIGN: Prospective study. METHODS: Patients who underwent femtosecond-assisted LASIK between February and April 2018 were included. Inclusion criteria were myopia from -1.00 to -8.00 diopters (D) and astigmatism up to -3.00 D and no previous surgeries. All patients were tested preoperatively and on day 1 and month 3 for uncorrected distance visual acuity (UDVA), manifest refraction, corrected distance visual acuity (CDVA), intraocular pressure (IOP), slitlamp and dilated fundus examination, Schirmer I test with anesthesia, and ocular surface disease index questionnaire. The FEMTO LDV Z8 was used for flap construction and the Wavelight Allegretto 400 excimer for refractive treatment. Flap thickness was measured at week 1 with anterior segment optical coherence tomography (AS-OCT). RESULTS: Eighty-two eyes were included. Logarithm of the minimum angle of resolution UDVA was 1.28 ± 0.53 preoperatively, 0.02 ± 0.05 at day 1, and 0.14 ± 0.127 at month 3. There was no loss of CDVA lines. The mean flap thickness measured at 1 week with AS-OCT was 73 ± 6.7 µm. CONCLUSIONS: The use of ultrathin flaps, just below Bowman's layer, with the Ziemer LDV Z8 femtosecond laser was possible, safe, reliable, and reproducible. Eighty-micron flaps allowed for excellent vision on 1 day post-LASIK and might be a good alternative to maintain an appropriate percentage of tissue altered, especially when attempting greater corrections or larger treatment zones.


Subject(s)
Astigmatism , Keratomileusis, Laser In Situ , Myopia , Astigmatism/surgery , Corneal Stroma/surgery , Humans , Lasers, Excimer/therapeutic use , Myopia/surgery , Prospective Studies , Refraction, Ocular , Retrospective Studies , Treatment Outcome
6.
J Photochem Photobiol B ; 212: 112047, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33045532

ABSTRACT

In this work, we present the maximum daily values of solar ultraviolet A radiation (UV-A) as a function of time. The results indicated that such values reached a maximum of 93.9 W/m2 in 2010 and a minimum of 16.5 W/m2 in 2012. The annual averages of both UV-A and solar ultraviolet B radiation (UV-B) from 2007 to 2013 were recorded. UV-A was always higher than UV-B. However, UV-B is more energetic due to its intrinsic wavelength. The nonmelanoma skin cancer mortality incidences per 100,000 inhabitants in Arica and in Chile as a function of time between 2007 and 2013 indicated that these mortality rates varied from 3.12 (Arica) to 0.88 (Chile) in 2007 and 2.71 (Arica) to 0.88 (Chile) in 2013. The nonmelanoma skin cancer prevalence rates per 100,000 inhabitants in Arica were 22.2 in 2007 and 19.5 in 2013. The relationship between NMSC and exposure to UV-A is given. In Arica, we report high levels of UV-A and the highest NMSC rates compared with other regions in our country.


Subject(s)
Neoplasms, Radiation-Induced/epidemiology , Skin Neoplasms/epidemiology , Ultraviolet Rays/adverse effects , Adult , Chile/epidemiology , Female , Humans , Male , Middle Aged , Neoplasms, Radiation-Induced/mortality , Prevalence , Skin Neoplasms/mortality , Young Adult
7.
Genome Biol Evol ; 12(9): 1516-1527, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32681795

ABSTRACT

Genome-wide association studies have uncovered thousands of genetic variants that are associated with a wide variety of human traits. Knowledge of how trait-associated variants are distributed within and between populations can provide insight into the genetic basis of group-specific phenotypic differences, particularly for health-related traits. We analyzed the genetic divergence levels for 1) individual trait-associated variants and 2) collections of variants that function together to encode polygenic traits, between two neighboring populations in Colombia that have distinct demographic profiles: Antioquia (Mestizo) and Chocó (Afro-Colombian). Genetic ancestry analysis showed 62% European, 32% Native American, and 6% African ancestry for Antioquia compared with 76% African, 10% European, and 14% Native American ancestry for Chocó, consistent with demography and previous results. Ancestry differences can confound cross-population comparison of polygenic risk scores (PRS); however, we did not find any systematic bias in PRS distributions for the two populations studied here, and population-specific differences in PRS were, for the most part, small and symmetrically distributed around zero. Both genetic differentiation at individual trait-associated single nucleotide polymorphisms and population-specific PRS differences between Antioquia and Chocó largely reflected anthropometric phenotypic differences that can be readily observed between the populations along with reported disease prevalence differences. Cases where population-specific differences in genetic risk did not align with observed trait (disease) prevalence point to the importance of environmental contributions to phenotypic variance, for both infectious and complex, common disease. The results reported here are distributed via a web-based platform for searching trait-associated variants and PRS divergence levels at http://map.chocogen.com (last accessed August 12, 2020).


Subject(s)
Genetic Predisposition to Disease , Genome, Human , Multifactorial Inheritance , Phenotype , Racial Groups/genetics , Colombia , Humans
8.
BMC Med Genet ; 21(Suppl 2): 132, 2020 06 25.
Article in English | MEDLINE | ID: mdl-32580712

ABSTRACT

BACKGROUND: Hispanic/Latino (HL) populations bear a disproportionately high burden of type 2 diabetes (T2D). The ability to predict T2D genetic risk using polygenic risk scores (PRS) offers great promise for improved screening and prevention. However, there are a number of complications related to the accurate inference of genetic risk across HL populations with distinct ancestry profiles. We investigated how ancestry affects the inference of T2D genetic risk using PRS in diverse HL populations from Colombia and the United States (US). In Colombia, we compared T2D genetic risk for the Mestizo population of Antioquia to the Afro-Colombian population of Chocó, and in the US, we compared European-American versus Mexican-American populations. METHODS: Whole genome sequences and genotypes from the 1000 Genomes Project and the ChocoGen Research Project were used for genetic ancestry inference and for T2D polygenic risk score (PRS) calculation. Continental ancestry fractions for HL genomes were inferred via comparison with African, European, and Native American reference genomes, and PRS were calculated using T2D risk variants taken from multiple genome-wide association studies (GWAS) conducted on cohorts with diverse ancestries. A correction for ancestry bias in T2D risk inference based on the frequencies of ancestral versus derived alleles was developed and applied to PRS calculations in the HL populations studied here. RESULTS: T2D genetic risk in Colombian and US HL populations is positively correlated with African and Native American ancestry and negatively correlated with European ancestry. The Afro-Colombian population of Chocó has higher predicted T2D risk than Antioquia, and the Mexican-American population has higher predicted risk than the European-American population. The inferred relative risk of T2D is robust to differences in the ancestry of the GWAS cohorts used for variant discovery. For trans-ethnic GWAS, population-specific variants and variants with same direction effects across populations yield consistent results. Nevertheless, the control for bias in T2D risk prediction confirms that explicit consideration of genetic ancestry can yield more reliable cross-population genetic risk inferences. CONCLUSIONS: T2D associations that replicate across populations provide for more reliable risk inference, and modeling population-specific frequencies of ancestral and derived risk alleles can help control for biases in PRS estimation.


Subject(s)
Diabetes Mellitus, Type 2/genetics , Genetic Predisposition to Disease , Hispanic or Latino/genetics , White People/genetics , Colombia , Diabetes Mellitus, Type 2/epidemiology , Genome-Wide Association Study , Humans , Polymorphism, Single Nucleotide/genetics , Prevalence , Risk Factors , United States
9.
Front Genet ; 10: 241, 2019.
Article in English | MEDLINE | ID: mdl-30967898

ABSTRACT

While genomic approaches to precision medicine hold great promise, they remain prohibitively expensive for developing countries. The precision public health paradigm, whereby healthcare decisions are made at the level of populations as opposed to individuals, provides one way for the genomics revolution to directly impact health outcomes in the developing world. Genomic approaches to precision public health require a deep understanding of local population genomics, which is still missing for many developing countries. We are investigating the population genomics of genetic variants that mediate drug response in an effort to inform healthcare decisions in Colombia. Our work focuses on two neighboring populations with distinct ancestry profiles: Antioquia and Chocó. Antioquia has primarily European genetic ancestry followed by Native American and African components, whereas Chocó shows mainly African ancestry with lower levels of Native American and European admixture. We performed a survey of the global distribution of pharmacogenomic variants followed by a more focused study of pharmacogenomic allele frequency differences between the two Colombian populations. Worldwide, we found pharmacogenomic variants to have both unusually high minor allele frequencies and high levels of population differentiation. A number of these pharmacogenomic variants also show anomalous effect allele frequencies within and between the two Colombian populations, and these differences were found to be associated with their distinct genetic ancestry profiles. For example, the C allele of the single nucleotide polymorphism (SNP) rs4149056 [Solute Carrier Organic Anion Transporter Family Member 1B1 (SLCO1B1)∗5], which is associated with an increased risk of toxicity to a commonly prescribed statin, is found at relatively high frequency in Antioquia and is associated with European ancestry. In addition to pharmacogenomic alleles related to increased toxicity risk, we also have evidence that alleles related to dosage and metabolism have large frequency differences between the two populations, which are associated with their specific ancestries. Using these findings, we have developed and validated an inexpensive allele-specific PCR assay to test for the presence of such population-enriched pharmacogenomic SNPs in Colombia. These results serve as an example of how population-centered approaches to pharmacogenomics can help to realize the promise of precision medicine in resource-limited settings.

10.
Rev. odontol. mex ; 22(3): 154-159, jul.-sep. 2018. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1014414

ABSTRACT

RESUMEN El labio y paladar hendido es una de las patologías congénitas con mayor prevalencia en el mundo. En el presente trabajo se hace un análisis de 12 PNU localizados en las secuencias genómicas de ABCA4, BMP4, MSX1, SUMO1, VAX1 y IRF6, bajo una perspectiva epidemiológica, de genética molecular, genómica y de genética de poblaciones; todo lo anterior aplicado a una población de Querétaro, México, de origen genético mixto. Material y métodos: Se realizó un estudio observacional, analítico y descriptivo a partir de muestras de 93 tríadas (sujetos de estudio y sus padres). Al seleccionar PNU que puedan ser diferenciados por medio de RFLP esperamos distinguir entre marcadores genéticos que: 1) cumplan con la ecuación de equilibrio de Hardy-Weinberg y 2) validarlos como potenciales marcadores genéticos para ser empleados en estudios de asociación en poblaciones cerradas de origen genético mixto con labio y paladar hendido (Amealco, Querétaro, México). De ser así, posteriormente se plantea probar las frecuencias obtenidas con una población seleccionada genéticamente cerrada de Amealco, Querétaro. Resultados: Después de realizar el análisis RFLP de 12 PNU localizados en la secuencia de genes ABCA4, BMP4, MSX1, SUMO1, VAX1 y IRF6, hallamos el mismo alelo para PNU analizado, el cual se encuentra en el 100% de la población. Conclusión: De los 12 PNU analizados, en este reporte, por primera vez se menciona la frecuencia de cinco de ellos. Los restantes siete presentaron la misma frecuencia reportada en la literatura. Aunque los PNU seleccionados no fueron de utilidad como marcadores genéticos debido a que el mismo alelo está presente en el 100% de la población general. El hecho de haberlos encontrado en el mismo genotipo de todas las muestras indica que la población de la ciudad de Querétaro es genéticamente cerrada y con base en esto extremadamente útil para futuras validaciones de otros PNU como posibles marcadores genéticos.


ABSTRACT The cleft lip and palate is one of the congenital pathologies with greater prevalence in the world. In the present work, there is an analysis of 12 SNP's located in genomic sequences of ABCA4, BMP4, MSX1, SUMO1, VAX1 andIRF6, under an epidemiological perspective, molecular genetics, genomics and population genetics. All of the above applied to a population of Queretaro, Mexico, of mixed genetic origin. Material and methods: A study was conducted of observation, analytic and descriptive study with samples from 93 triads (study subjects and their parents). When you select SNP's that can be differentiated by RFLP (Restriction Fragment Length Polymorphism)we hope to distinguish between genetic markers that: 1)comply with the equation of balance of Hardy-Weiner and 2) Validate them as potential genetic markers to be used in studies of association in closed populations of genetic origin mixed with cleft lip and palate in Amealco, Queretaro, Mexico. If so subsequently raises test the frequencies obtained with a selected population genetically closed in Amealco, Queretaro. Results: After performing the RFLP analysis of 12 SNP's located in the sequence of genes ABCA4, BMP4, MSX1, SUMO1, VAX1 and IRF6, we find the same allele for SNP analyzed which is located in the 100% of the population. Conclusion: Of the 12 SNP's analyzed in this report, for the fi rst time 5 of them are mentioned their frequency. The rest of them had the same frequency reported in the literature. Although the SNP's selected were not useful as a genetic markers due to the same allele is present in 100% of the general population. The fact of having found in the same genotype of all samples indicates that the population of the city of Queretaro is genetically closed and on the basis of this extremely useful for future validations of other SNP's as potential genetic markers.

11.
Arthritis Rheumatol ; 70(4): 594-605, 2018 04.
Article in English | MEDLINE | ID: mdl-29287303

ABSTRACT

OBJECTIVE: The nuclear oncoprotein DEK is an autoantigen associated with juvenile idiopathic arthritis (JIA), especially the oligoarticular subtype. DEK is a secreted chemotactic factor. Abundant levels of DEK and DEK autoantibodies are found in inflamed synovium in JIA. We undertook this study to further characterize the nature of DEK autoantibodies in screening serum samples from 2 different cohorts that consisted mostly of patients with JIA. METHODS: DEK autoantibody levels were analyzed in sera from 33 JIA patients, 13 patients with other inflammatory conditions, and 11 healthy controls, as well as in 89 serum samples from JIA patients receiving anti-tumor necrosis factor (anti-TNF) therapy. Recombinant His-tagged full-length DEK protein (1-375 amino acids [aa]) and the 187-375-aa and 1-350-aa His-tagged DEK fragments made in a baculovirus system were used for enzyme-linked immunosorbent assay (ELISA) and immunoblotting. The C-terminal 25-aa fragment of DEK was expressed in a glutathione S-transferase-tagged vector. ELISA results were calculated as area under the curve by the trapezoidal rule. RESULTS: DEK autoantibody levels were significantly higher in patients with polyarticular JIA than in those with oligoarticular JIA, and were higher in patients with polyarticular JIA who had more active disease after cessation of anti-TNF therapy. Immunoblotting against the C-terminal 25-aa fragment of DEK confirmed that this section of the DEK molecule is the most immunogenic domain. CONCLUSION: DEK autoantibody levels are higher in patients with polyarticular JIA than in those with oligoarticular JIA, and higher in patients who have disease flares after cessation of anti-TNF therapy. The C-terminal 25-aa fragment is the most immunogenic portion of DEK. These findings are significant with respect to the nature of DEK autoantibodies, their contribution to JIA pathogenesis, and their implications for JIA management.


Subject(s)
Antirheumatic Agents/immunology , Arthritis, Juvenile/blood , Autoantibodies/blood , Chromosomal Proteins, Non-Histone/immunology , Oncogene Proteins/immunology , Poly-ADP-Ribose Binding Proteins/immunology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adolescent , Arthritis, Juvenile/drug therapy , Arthritis, Juvenile/immunology , Autoantibodies/immunology , Case-Control Studies , Child , Female , Humans , Male , Symptom Flare Up , Withholding Treatment
12.
Sci Rep ; 7(1): 17127, 2017 12 07.
Article in English | MEDLINE | ID: mdl-29215035

ABSTRACT

Differences in genetic ancestry and socioeconomic status (SES) among Latin American populations have been linked to health disparities for a number of complex diseases, such as diabetes. We used a population genomic approach to investigate the role that genetic ancestry and socioeconomic status (SES) play in the epidemiology of type 2 diabetes (T2D) for two Colombian populations: Chocó (Afro-Latino) and Antioquia (Mestizo). Chocó has significantly higher predicted genetic risk for T2D compared to Antioquia, and the elevated predicted risk for T2D in Chocó is correlated with higher African ancestry. Despite its elevated predicted genetic risk, the population of Chocó has a three-times lower observed T2D prevalence than Antioquia, indicating that environmental factors better explain differences in T2D outcomes for Colombia. Chocó has substantially lower SES than Antioquia, suggesting that low SES in Chocó serves as a protective factor against T2D. The combination of lower prevalence of T2D and lower SES in Chocó may seem surprising given the protective nature of elevated SES in many populations in developed countries. However, low SES has also been documented to be a protective factor in rural populations in less developed countries, and this appears to be the case when comparing Chocó to Antioquia.


Subject(s)
Diabetes Mellitus, Type 2/genetics , Genetic Predisposition to Disease , Colombia , Diabetes Mellitus, Type 2/epidemiology , Humans , Pedigree , Prevalence , Socioeconomic Factors
13.
G3 (Bethesda) ; 7(10): 3435-3447, 2017 10 05.
Article in English | MEDLINE | ID: mdl-28855283

ABSTRACT

At least 20% of Colombians identify as having African ancestry, yielding the second largest population of Afro-descendants in Latin America. To date, there have been relatively few studies focused on the genetic ancestry of Afro-Latino populations. We report a comparative analysis of the genetic ancestry of Chocó, a state located on Colombia's Pacific coast with a population that is >80% Afro-Colombian. We compared genome-wide patterns of genetic ancestry and admixture for Chocó to six other admixed American populations, with an emphasis on a Mestizo population from the nearby Colombian city of Medellín. One hundred sample donors from Chocó were genotyped across 610,545 genomic sites and compared with 94 publicly available whole genome sequences from Medellín. At the continental level, Chocó shows mostly African genetic ancestry (76%) with a nearly even split between European (13%) and Native American (11%) fractions, whereas Medellín has primarily European ancestry (75%), followed by Native American (18%) and African (7%). Sample donors from Chocó self-identify as having more African ancestry, and conversely less European and Native American ancestry, than can be genetically inferred, as opposed to what we previously found for Medellín, where individuals tend to overestimate levels of European ancestry. We developed a novel approach for subcontinental ancestry assignment, which allowed us to characterize subcontinental source populations for each of the three distinct continental ancestry fractions separately. Despite the clear differences between Chocó and Medellín at the level of continental ancestry, the two populations show overall patterns of subcontinental ancestry that are highly similar. Their African subcontinental ancestries are only slightly different, with Chocó showing more exclusive shared ancestry with the modern Yoruba (Nigerian) population, and Medellín having relatively more shared ancestry with West African populations in Sierra Leone and Gambia. Both populations show very similar Spanish ancestry within Europe and virtually identical patterns of Native American ancestry, with main contributions from the Embera and Waunana tribes. When the three subcontinental ancestry components are considered jointly, the populations of Chocó and Medellín are shown to be most closely related, to the exclusion of the other admixed American populations that we analyzed. We consider the implications of the existence of shared subcontinental ancestries for Colombian populations that appear, at first glance, to be clearly distinct with respect to competing notions of national identity that emphasize ethnic mixing (mestizaje) vs. group-specific identities (multiculturalism).


Subject(s)
Black People/genetics , White People/genetics , Colombia , Ethnicity/genetics , Genetics, Population , Genome, Human , Humans
14.
Oncol Lett ; 13(5): 3787-3792, 2017 May.
Article in English | MEDLINE | ID: mdl-28521479

ABSTRACT

Vitamin D synthesis takes place in the skin due to solar ultraviolet-B (UVB) radiation. Several studies have shown the association between low sun exposure, non-melanoma skin cancer (NMSC) and a lack of vitamin D synthesis. Since such synthesis in the body depends on the exposure of the skin to solar UVB radiation (290-320 nm), experimental measurements of this type of solar radiation are important. Tarapaca University in Arica, Chile, established a solar UV radiation laboratory in 2006 and since then this laboratory has performed systematic experimental solar UVB measurements using a calibrated biometer instrument. The results, which are presented in the current study, showed the association between NMSC and MSC rates, and the time required to produce 1,000 IU vitamin D with latitudinal variation. Solar UV index (UVI) levels reported in 6 cities from the north to the south of Chile indicated that the UVI ratio of monthly mean values was 1.8 times higher in Arica than in Punta Arenas in January (summer in Chile), whereas it was 14 times higher in June (winter). This factor is an important consideration, since vitamin D synthesis is directly associated with the exposure of individuals to solar UVB radiation. A similar trend was observed in Antofagasta, Santiago, Concepcion, Valdivia and Punta Arenas. It can be concluded from these data that there is a direct association between NMSC rates and mortality, and UVB radiation, meaning that this type of cancer would not depend on vitamin D synthesis and therefore on calcium uptake. By contrast, MSC rates increased with decreased levels of vitamin D, and thus calcium uptake, in all cities, with the only exception being Punta Arenas.

16.
Rev Biodivers Neotrop ; 6(1): 45-54, 2016.
Article in English | MEDLINE | ID: mdl-27668076

ABSTRACT

OBJECTIVE: Chocó is a state located on the Pacific coast of Colombia that has a majority Afro-Colombian population. The objective of this study was to characterize the genetic ancestry, admixture and diversity of the population of Chocó, Colombia. METHODOLOGY: Genetic variation was characterized for a sample of 101 donors (61 female and 40 male) from the state of Chocó. Genotypes were determined for each individual via the characterization of 610,545 single nucleotide polymorphisms genome-wide. Haplotypes for the uniparental mitochondrial DNA (female) and Y-DNA (male) chromosomes were also determined. These data were used for comparative analyses with a number of worldwide populations, including putative ancestral populations from Africa, the Americas and Europe, along with several admixed American populations. RESULTS: The population of Chocó has predominantly African genetic ancestry (75.8%) with approximately equal parts European (13.4%) and Native American (11.1%) ancestry. Chocó shows relatively high levels of three-way genetic admixture, and far higher levels of Native American ancestry, compared to other New World African populations from the Caribbean and the United States. There is a striking pattern of sex-specific ancestry in Chocó, with Native American admixture along the female lineage and European admixture along the male lineage. The population of Chocó is also characterized by relatively high levels of overall genetic diversity compared to both putative ancestral populations and other admixed American populations. CONCLUSION: These results suggest a unique genetic heritage for the population of Chocó and underscore the profound human genetic diversity that can be found in the region.

18.
Oncol Lett ; 10(4): 2259-2264, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26622830

ABSTRACT

The danger of overexposure to solar ultraviolet radiation has been widely reviewed since the 1980s due to the depletion of the ozone layer. However, the benefits of mild exposure of the skin to ultraviolet (UV) light have not been widely investigated. Numerous reports have demonstrated that an association exists between low light exposure to the sun, non-melanoma skin cancer and a lack of vitamin D synthesis. As vitamin D synthesis in the body depends on skin exposure to UVB radiation from the sun (wavelength, 290-320 nm), experimental measurements for this type of solar radiation are important. The present study analyzed data obtained from a laboratory investigating UV radiation from the sun at the University of Tarapacá (Arica, Chile), where systematic experimental UVB measurements had been performed using a calibrated biometer instrument since 2006. These data were compared with skin cancer data from the local population. The results demonstrated that the incidence of skin cancer systematically increased from 7.4 to 18.7 in men and from 10.0 to 21.7 in women between 2000 and 2006 in Arica, respectively; this increase may be due to multiple factors, including the lack of adequate levels of vitamin D in risk groups such as post-menopausal women and senior age. This marked increase may also be due to the high levels of UV radiation measured in this region throughout the year. However, it is not certain that the local population has adequate vitamin D levels, nor that their skin has been predominantly exposed to artificial light that does not allow adequate vitamin D synthesis. Thus, the current study presents the association between skin type IV, the time to induce solar erythema and the time required to produce 1,000 international units of vitamin D.

19.
Oncol Lett ; 7(2): 483-486, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24396474

ABSTRACT

The present study analyzed the risk of skin cancer due to ultraviolet erythemal irradiance (UVery) in Arica, Chile, using measurements of the solar ultraviolet index (UVI) between 2006 and 2011. The daily maximum value by biometer Yankee Environmental Systems (YES) solar ultraviolet B (UVB)-1 was measured between 2007 and 2012, and seasonal variations were clearly observed, with higher UVI levels during the summer when UVI usually reached extreme values of >11. The maximum UVI value was 15.6 in the summer of 2008 and the minimum was 2.2 in the winter of 2008. The UVI mean values that were collected monthly at noon between 2006 and 2010 fluctuated between 13 and 6, and reached higher values in January and lower values in June and July. Thus, a seasonal UVI response was observed during the two seasons. The accumulated UVery/day was calculated between September 2006 and 2007, the time when Arica normally receives the highest UVI levels. It was also noted that 60% of the days in September demonstrated values of >3.41 kJ/m2/day, while 3.3% of cloudy days had values of <2.0 kJ/m2/day. The mean value of UVery during 2007 was 3.23 kJ/m2/day and the variation was 1.9-4.6 kJ/m2/day. These UVery values were several times higher than the minimal erythemal doses (MEDs) corresponding to the skin types most frequently observed in Chile, skin types III and IV. The MED for skin type IV was 0.60 kJ/m2. The results demonstrated that the skin cancer rate was increased due to the fact that individuals from Arica are exposed to several times more UVery than the MED for their skin type during the spring and summer seasons.

20.
Oncol Lett ; 3(4): 893-896, 2012 Apr 01.
Article in English | MEDLINE | ID: mdl-22741013

ABSTRACT

An increase in the amount of solar ultraviolet light that reaches the Earth is considered to be responsible for the worldwide increase in skin cancer. It has been reported that exposure to excessive levels of solar ultraviolet light has multiple effects, which can be harmful to humans. Experimental ultraviolet light measurements were obtained in several locations in Chile between 2006 and 2009 using wide-band solar light Biometer YES, calibrated according to World Meteorological Organization (WMO) criteria and integrated into the National Meteorological Center of Chile ultraviolet network (DMC). The aim of this study was to determine skin cancer rates in relation to experimental data accumulated during one year of studying the solar ultraviolet index in Chile, in order to explain the possible effect of radiation on skin cancer. The rate of skin cancer per 100,000 persons was considered in Arica, Santiago, Concepción and Valdivia and extrapolated to other cities. Results of the present study showed that the incidence of skin cancer was markedly correlated with accumulative ultraviolet radiation, and rates of skin cancer could be extrapolated to other locations in Chile. There is a steady increase in the rate of skin cancer in cities located nearest to the equator (low latitude) that receive greater accumulated solar ultraviolet radiation, due to the accumulative effects of this type of radiation on the skin. It can be concluded that Arica is a city at sea level that receives higher levels of ultraviolet solar radiation than other locations, which may explain the higher prevalence of skin cancer in the population of this location, compared with other cities in Chile.

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