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1.
Biosensors (Basel) ; 14(1)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275305

RESUMO

This study examines the relationship between physiological complexity, as measured by Approximate Entropy (ApEn) and Sample Entropy (SampEn), and fitness levels in female athletes. Our focus is on their association with maximal oxygen consumption (VO2,max). Our findings reveal a complex relationship between entropy metrics and fitness levels, indicating that higher fitness typically, though not invariably, correlates with greater entropy in physiological time series data; however, this is not consistent for all individuals. For Heart Rate (HR), entropy measures suggest stable patterns across fitness categories, while pulse oximetry (SpO2) data shows greater variability. For instance, the medium fitness group displayed an ApEn(HR) = 0.57±0.13 with a coefficient of variation (CV) of 22.17 and ApEn(SpO2) = 0.96±0.49 with a CV of 46.08%, compared to the excellent fitness group with ApEn(HR) = 0.60±0.09 with a CV of 15.19% and ApEn(SpO2) =0.85±0.42 with a CV of 49.46%, suggesting broader physiological responses among more fit individuals. The larger standard deviations and CVs for SpO2 entropy may indicate the body's proficient oxygen utilization at higher levels of physical demand. Our findings advocate for combining entropy metrics with wearable sensor technology for improved biomedical analysis and personalized healthcare.


Assuntos
Oximetria , Oxigênio , Humanos , Feminino , Entropia , Exercício Físico
2.
Sensors (Basel) ; 22(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35591092

RESUMO

Nowadays, pulse oximetry has become the standard in primary and intensive care units, especially as a triage tool during the current COVID-19 pandemic. Hence, a deeper understanding of the measurement errors that can affect precise readings is a key element in clinical decision-making. Several factors may influence the accuracy of pulse oximetry, such as skin color, body temperature, altitude, or patient movement. The skin pigmentation effect on pulse oximetry accuracy has long been studied reporting some contradictory conclusions. Recent studies have shown a positive bias in oxygen saturation measurements in patients with darkly pigmented skin, particularly under low saturation conditions. This review aims to study the literature that assesses the influence of skin pigmentation on the accuracy of these devices. We employed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to conduct a systematic review retrospectively since February 2022 using WOS, PubMed, and Scopus databases. We found 99 unique references, of which only 41 satisfied the established inclusion criteria. A bibliometric and scientometrics approach was performed to examine the outcomes of an exhaustive survey of the thematic content and trending topics.


Assuntos
COVID-19 , Pigmentação da Pele , Bibliometria , Humanos , Oximetria , Oxigênio , Pandemias , Estudos Retrospectivos
3.
Hepatology ; 73(5): 1783-1796, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32893372

RESUMO

BACKGROUND AND AIMS: Gallbladder cancer (GBC) is a neglected disease with substantial geographical variability: Chile shows the highest incidence worldwide, while GBC is relatively rare in Europe. Here, we investigate the causal effects of risk factors considered in current GBC prevention programs as well as C-reactive protein (CRP) level as a marker of chronic inflammation. APPROACH AND RESULTS: We applied two-sample Mendelian randomization (MR) using publicly available data and our own data from a retrospective Chilean and a prospective European study. Causality was assessed by inverse variance weighted (IVW), MR-Egger regression, and weighted median estimates complemented with sensitivity analyses on potential heterogeneity and pleiotropy, two-step MR, and mediation analysis. We found evidence for a causal effect of gallstone disease on GBC risk in Chileans (P = 9 × 10-5 ) and Europeans (P = 9 × 10-5 ). A genetically elevated body mass index (BMI) increased GBC risk in Chileans (P = 0.03), while higher CRP concentrations increased GBC risk in Europeans (P = 4.1 × 10-6 ). European results suggest causal effects of BMI on gallstone disease (P = 0.008); public Chilean data were not, however, available to enable assessment of the mediation effects among causal GBC risk factors. CONCLUSIONS: Two risk factors considered in the current Chilean program for GBC prevention are causally linked to GBC risk: gallstones and BMI. For Europeans, BMI showed a causal effect on gallstone risk, which was itself causally linked to GBC risk.


Assuntos
Índice de Massa Corporal , Proteína C-Reativa/análise , Neoplasias da Vesícula Biliar/etiologia , Cálculos Biliares/complicações , Adulto , Fatores Etários , Chile/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Neoplasias da Vesícula Biliar/epidemiologia , Neoplasias da Vesícula Biliar/genética , Cálculos Biliares/epidemiologia , Predisposição Genética para Doença/genética , Variação Genética , Humanos , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco
4.
Cancer Epidemiol ; 65: 101643, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32058310

RESUMO

BACKGROUND: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence. METHODS: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication. RESULTS: Our results confirmed the reported associations for Chileans with similar risk effects. Particularly strong associations (per-allele odds ratios close to 2) were observed for Chileans with high Native American (=Mapuche) ancestry. No associations were noticed for Europeans, but the statistical power was low. CONCLUSION: Taking full advantage of genetic and ethnic differences in GBC risk may improve the efficiency of current prevention programs.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Neoplasias da Vesícula Biliar/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Chile/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Neoplasias da Vesícula Biliar/epidemiologia , Estudos de Associação Genética , Humanos , Indígenas Sul-Americanos/genética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , População Branca/genética
5.
Nat Commun ; 9(1): 5388, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30568240

RESUMO

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.


Assuntos
Migração Humana , Indígenas Norte-Americanos/genética , Indígenas Sul-Americanos/genética , Haplótipos , Humanos , México , Nariz/anatomia & histologia , América do Sul
6.
Sci Rep ; 8(1): 963, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29343858

RESUMO

Facial asymmetries are usually measured and interpreted as proxies to developmental noise. However, analyses focused on its developmental and genetic architecture are scarce. To advance on this topic, studies based on a comprehensive and simultaneous analysis of modularity, morphological integration and facial asymmetries including both phenotypic and genomic information are needed. Here we explore several modularity hypotheses on a sample of Latin American mestizos, in order to test if modularity and integration patterns differ across several genomic ancestry backgrounds. To do so, 4104 individuals were analyzed using 3D photogrammetry reconstructions and a set of 34 facial landmarks placed on each individual. We found a pattern of modularity and integration that is conserved across sub-samples differing in their genomic ancestry background. Specifically, a signal of modularity based on functional demands and organization of the face is regularly observed across the whole sample. Our results shed more light on previous evidence obtained from Genome Wide Association Studies performed on the same samples, indicating the action of different genomic regions contributing to the expression of the nose and mouth facial phenotypes. Our results also indicate that large samples including phenotypic and genomic metadata enable a better understanding of the developmental and genetic architecture of craniofacial phenotypes.


Assuntos
Face/anatomia & histologia , Face/fisiologia , Desenvolvimento Maxilofacial/genética , Adolescente , Adulto , Feminino , Estudo de Associação Genômica Ampla/métodos , Humanos , América Latina , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem
7.
PLoS Genet ; 13(5): e1006756, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28542165

RESUMO

Latin Americans are highly heterogeneous regarding the type of Native American ancestry. Consideration of specific associations with common diseases may lead to substantial advances in unraveling of disease etiology and disease prevention. Here we investigate possible associations between the type of Native American ancestry and leading causes of death. After an aggregate-data study based on genome-wide genotype data from 1805 admixed Chileans and 639,789 deaths, we validate an identified association with gallbladder cancer relying on individual data from 64 gallbladder cancer patients, with and without a family history, and 170 healthy controls. Native American proportions were markedly underestimated when the two main types of Native American ancestry in Chile, originated from the Mapuche and Aymara indigenous peoples, were combined together. Consideration of the type of Native American ancestry was crucial to identify disease associations. Native American ancestry showed no association with gallbladder cancer mortality (P = 0.26). By contrast, each 1% increase in the Mapuche proportion represented a 3.7% increased mortality risk by gallbladder cancer (95%CI 3.1-4.3%, P = 6×10-27). Individual-data results and extensive sensitivity analyses confirmed the association between Mapuche ancestry and gallbladder cancer. Increasing Mapuche proportions were also associated with an increased mortality due to asthma and, interestingly, with a decreased mortality by diabetes. The mortality due to skin, bladder, larynx, bronchus and lung cancers increased with increasing Aymara proportions. Described methods should be considered in future studies on human population genetics and human health. Complementary individual-based studies are needed to apportion the genetic and non-genetic components of associations identified relying on aggregate-data.


Assuntos
Neoplasias da Vesícula Biliar/genética , Estudo de Associação Genômica Ampla , Indígenas Norte-Americanos/genética , Adolescente , Adulto , Chile , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Genética Populacional , Genoma Humano , Genótipo , Humanos , América Latina/epidemiologia , Masculino , Fatores de Risco
8.
Rev Med Chil ; 143(4): 439-43, 2015 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-26204534

RESUMO

BACKGROUND: Amerindian admixture is an important parameter to consider in epidemiological studies in American countries, to make a proper selection of cases and controls. AIM: To compare Amerindian admixture estimates obtained using ABO*A and ABO*O blood group alleles and ancestral identity markers (AIMs) in the mixed Chilean population. SUBJECTS AND METHODS: Amerindian admixture rates were determined in 720 Chilean volunteers residing in Arica and born in the 15 regions of the country, using ABO*O and ABO*A alleles and 40 AIMs selected from more than 500,000 single nucleotide polymorphisms (SNPs). RESULTS: Mean admixture estimates obtained using ABO*O and ABO*A alleles and AIMs were 35, 47% and 48% respectively. There was concordance in estimates, with the exception of the admixture based on ABO*O allele and AIMs. CONCLUSIONS: In Chile, Amerindian admixture estimates obtained using ABO*A could be used as an alternative to AIMs in justified cases provided the sample size is reasonably large.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Indígenas Sul-Americanos/genética , População Branca/genética , Chile/etnologia , Feminino , Frequência do Gene/genética , Marcadores Genéticos/genética , Genética Populacional , Humanos , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes
9.
PLoS One ; 10(4): e0121834, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25885573

RESUMO

Studies performed in the Andean plateau, one of the highest inhabited areas in the world, have reported that reduced availability of oxygen is associated to fetal growth retardation and lower birth weight, which are established predictors of morbidity and mortality during the first year of life. To test this hypothesis, perinatal variables of neonates born at the Juan Noé Hospital of Arica, Chile, were analyzed in relation to altitude of residence and Aymara ancestry of their mothers. The study population comprised the offspring of 5,295 mothers born between February 2004 and August 2010. Information included birth weight, height, head circumference, gestational age, altitude of residence and socioeconomic status, and was obtained from medical records. Mother´s ancestry was assessed based on surnames which were linked to percentages of Aymara admixture estimates relying on 40 selected ancestry informative markers. After correcting for the effect of multicollinearity among predictor variables, neonates born to mothers with an increased component of Aymara ancestry showed significantly higher birth weight and height at sea level, a marginally significant (p-value 0.06) decrease of birth weight and a significant decrease of height with altitude in comparison with the offspring of mothers with low Aymara ancestry. Since observed tendencies are suggestive of a possible genetic adaptation to hypoxia of the Chilean Aymara, we discuss briefly preliminary evidence related to fetal oxygen transport, particularly polymorphisms in the promoters of the HBG1 and HBG2 genes that are modulators of HbF synthesis, obtained in this ethnic group.


Assuntos
Altitude , Peso ao Nascer/fisiologia , Tamanho Corporal/fisiologia , Adaptação Fisiológica , Adolescente , Adulto , Chile , Feminino , Hemoglobina Fetal/metabolismo , Idade Gestacional , Cabeça/fisiologia , Humanos , Hipóxia , Indígenas Sul-Americanos/genética , Recém-Nascido , Masculino , Mães , Polimorfismo Genético , Regiões Promotoras Genéticas , Análise de Regressão , Estudos Retrospectivos , Classe Social , Adulto Jovem , gama-Globinas/genética
10.
Rev. méd. Chile ; 143(4): 439-443, abr. 2015. tab
Artigo em Espanhol | LILACS | ID: lil-747549

RESUMO

Background: Amerindian admixture is an important parameter to consider in epidemiological studies in American countries, to make a proper selection of cases and controls. Aim: To compare Amerindian admixture estimates obtained using ABO*A and ABO*O blood group alleles and ancestral identity markers (AIMs) in the mixed Chilean population. Subjects and Methods: Amerindian admixture rates were determined in 720 Chilean volunteers residing in Arica and born in the 15 regions of the country, using ABO*O and ABO*A alleles and 40 AIMs selected from more than 500,000 single nucleotide polymorphisms (SNP´s). Results: Mean admixture estimates obtained using ABO*O and ABO*A alleles and AIM s were 35, 47% and 48% respectively. There was concordance in estimates, with the exception of the admixture based on ABO*O allele and AIMs. Conclusions: In Chile, Amerindian admixture estimates obtained using ABO*A could be used as an alternative to AIMs in justified cases provided the sample size is reasonably large.


Assuntos
Feminino , Humanos , Masculino , Sistema ABO de Grupos Sanguíneos/genética , População Branca/genética , Indígenas Sul-Americanos/genética , Chile/etnologia , Frequência do Gene/genética , Marcadores Genéticos/genética , Genética Populacional , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes
11.
Rev Med Chil ; 142(8): 961-5, 2014 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-25424667

RESUMO

BACKGROUND: Studies performed in Andean populations living in high altitude, indicate that the reduced availability of oxygen could be associated to both a fetal growth retardation and a lower birth weight. These variables are predictive of morbidity and mortality during the first year of life. AIM: To study perinatal variables of newborns of mothers living at contrasting altitudinal levels, harboring different degrees of Aymara ancestry. SUBJECTS AND METHODS: Review of medical records of 5,295 women whose deliveries occurred between February 2004 and August 2010. Information was obtained on place of residence, grouped into two categories: coast (150 to 3,000 m) and high plateau (3,000 to 4,300 m), ancestry was estimated using number of Aymara surnames that were homologated to percentages of Amerindian admixture, gestational age, birth weight, height, head circumference and obstetric variables. RESULTS: Gestational age showed a tendency to increase and birth weight, height and head circumference to decrease with altitude of residence. Only weight reached statistical significance. Women with Aymara ancestry gave birth to children with a significantly higher gestational age, weight and cranial circumference. CONCLUSIONS: Altitude of residence is related to a decrease in perinatal variables that proved to be less pronounced in newborns of mothers with a higher degree of Aymara ancestry. RESULTS suggest a genetic adaptation to hypoxia that could be related to candidate genes linked to the capture, transport or utilization of oxygen.


Assuntos
Adaptação Fisiológica/genética , Altitude , Peso ao Nascer/genética , Estatura/genética , Desenvolvimento Fetal/genética , Indígenas Sul-Americanos/genética , Adolescente , Adulto , Estudos Transversais , Feminino , Geografia Médica , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Adulto Jovem
12.
Rev. méd. Chile ; 142(8): 961-965, ago. 2014. tab
Artigo em Espanhol | LILACS | ID: lil-728343

RESUMO

Background: Studies performed in Andean populations living in high altitude, indicate that the reduced availability of oxygen could be associated to both a fetal growth retardation and a lower birth weight. These variables are predictive of morbidity and mortality during the first year of life. Aim: To study perinatal variables of newborns of mothers living at contrasting altitudinal levels, harboring different degrees of Aymara ancestry. Subjects and Methods: Review of medical records of 5,295 women whose deliveries occurred between February 2004 and August 2010. Information was obtained on place of residence, grouped into two categories: coast (150 to 3,000 m) and high plateau (3,000 to 4,300 m), ancestry was estimated using number of Aymara surnames that were homologated to percentages of Amerindian admixture, gestational age, birth weight, height, head circumference and obstetric variables. Results: Gestational age showed a tendency to increase and birth weight, height and head circumference to decrease with altitude of residence. Only weight reached statistical significance. Women with Aymara ancestry gave birth to children with a significantly higher gestational age, weight and cranial circumference. Conclusions: Altitude of residence is related to a decrease in perinatal variables that proved to be less pronounced in newborns of mothers with a higher degree of Aymara ancestry. Results suggest a genetic adaptation to hypoxia that could be related to candidate genes linked to the capture, transport or utilization of oxygen.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Adulto Jovem , Adaptação Fisiológica/genética , Altitude , Peso ao Nascer/genética , Estatura/genética , Desenvolvimento Fetal/genética , Indígenas Sul-Americanos/genética , Estudos Transversais , Geografia Médica , Idade Gestacional
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