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1.
PeerJ ; 12: e16797, 2024.
Article in English | MEDLINE | ID: mdl-38529306

ABSTRACT

The topographical, geological, climatic and biodiversity complexity of Mesoamerica has made it a primary research focus. The Mesoamerican highlands is a region with particularly high species richness and within-species variation. The Cinnamon-bellied Flowerpiercer, Diglossa baritula (Wagler, 1832), is a species endemic to the Mesoamerican highlands, with three allopatric subspecies currently recognized. To characterize divergence within this species, we integrated genomics, morphology, coloration and ecological niche modeling approaches, obtained from sampling individuals across the entire geographic distribution of the species. Our results revealed a clear genomic divergence between the populations to the east versus the west of the Isthmus of Tehuantepec. In contrast to the genomic results, morphology and coloration analyses showed intermediate levels of differentiation, indicating that population groups within D. baritula have probably been under similar selective pressures. Our morphology results indicated that the only sexually dimorphic morphological variable is the wing chord, with males having a longer wing chord than females. Finally, ecological data indicated that there are differences in ecological niche within D. baritula. Our data suggest that D. baritula could contain two or more incipient species at the intermediate phase of the speciation continuum. These results highlight the importance of the geographical barrier of the Isthmus of Tehuantepec and Pleistocene climatic events in driving isolation and population divergence in D. baritula. The present investigation illustrates the speciation potential of the D. baritula complex and the capacity of Mesoamerican highlands to create cryptic biodiversity and endemism.


Subject(s)
Birds , Ecosystem , Animals , Female , Male , Biodiversity , Geography , Phylogeny
2.
Zookeys ; 1188: 169-195, 2024.
Article in English | MEDLINE | ID: mdl-38230381

ABSTRACT

Factors such as the Andean uplift, Isthmus of Panama, and climate changes have influenced bird diversity in the Neotropical region. Studying bird species that are widespread in Neotropical highlands and lowlands can help us understand the impact of these factors on taxa diversification. Our main objectives were to determine the biogeographic factors that contributed to the diversification of Euphoniinae and re-evaluate their phylogenetic relationships. The nextRAD and mitochondrial data were utilized to construct phylogenies. The ancestral distribution range was then estimated using a time-calibrated phylogeny, current species ranges, and neotropical regionalization. The phylogenies revealed two main Euphoniinae clades, Chlorophonia and Euphonia, similar to previous findings. Furthermore, each genus has distinctive subclades corresponding to morphology and geography. The biogeographic results suggest that the Andean uplift and the establishment of the western Amazon drove the vicariance of Chlorophonia and Euphonia during the Miocene. The Chlorophonia lineage originated in the Andes mountains and spread to Central America and the Mesoamerican highlands after the formation of the Isthmus of Panama. Meanwhile, the ancestral area of Euphonia was the Amazonas, from which it spread to trans-Andean areas during the Pliocene and Pleistocene due to the separation of the west lowlands from Amazonas due to the Northern Andean uplift. Chlorophonia and Euphonia species migrated to the Atlantic Forest during the Pleistocene through corridors from the East Andean Humid Forest and Amazonas. These two genera had Caribbean invasions with distinct geographic origins and ages. Finally, we suggested taxonomic changes in the genus Euphonia based on the study's phylogenetic, morphological, and biogeographic findings.

3.
Article in English | MEDLINE | ID: mdl-36141695

ABSTRACT

People living with HIV/AIDS not only suffer in terms of physical and/or psychological health, but also frequently experience violations of human rights and fundamental freedoms. Although there are international treaties and a regulatory framework that legally protects people with HIV/AIDS, it is essential to determine the effectiveness of the regulatory framework in Colombia. Therefore, our main goal was to examine the legislation on HIV/AIDS in Colombia with the purpose of understanding the decrees and laws, and describing the main obstacles and barriers that people with HIV/AIDS encounter. For this purpose, we employed the method of legal interpretation and reviewed the legal regulations on HIV/AIDS, as well as the judgments of guardianship of the Constitutional Court. It is verified that there is a specific regulation on HIV/AIDS, specifically decree 559 of 19,991, decree 1543 of 1997, Law 599 of 2000, Law 972 of 2005, and Law 1220 of 2008. Although at the legislative level Colombia shows an evolution in the norm, patients with HIV/AIDS continue to be victims of human rights violations. As a result, and through the analysis of tutela judgments, it was found that the Constitutional Court recognized the violation of rights and ordered the necessary measures to be taken to guarantee the human rights and fundamental freedoms of the defendants.


Subject(s)
Acquired Immunodeficiency Syndrome , HIV Infections , Acquired Immunodeficiency Syndrome/prevention & control , Colombia , HIV Infections/prevention & control , Human Rights , Humans , International Cooperation
4.
PeerJ ; 10: e12901, 2022.
Article in English | MEDLINE | ID: mdl-35198262

ABSTRACT

Animals derive their coloration from a variety of pigments as well as non-pigmentary structural features. One of the most widespread types of pigments are carotenoids, which are used by all invertebrate taxa and most vertebrate orders to generate red, pink, orange and yellow coloration. Despite their widespread use by diverse animal groups, animals obligately obtain carotenoid pigments from diet. Carotenoid-based coloration is therefore modulated by evolutionary and ecological processes that affect the acquisition and deposition of these pigments into tegumentary structures. The Flame-colored Tanager (Piranga bidentata) is a highland songbird in the cardinal family (Cardinalidae) that is distributed from Mexican sierras through Central America up to western Panama. While female plumage throughout its entire range is predominantly yellow, males exhibit a noticeable split in ventral plumage color, which is bright orange on the West slope and the Tres Marias Islands and blood red in Eastern Mexico and Central America. We used Multiple Regression on Matrices (MRM) to evaluate the relative contributions of geographic distance, climate and genetic distance on color divergence and body differences between geographically disjunct populations. We found that differentiation in carotenoid plumage coloration was mainly explained by rainfall differences between disjunct populations, whereas body size differences was best explained by variation in the annual mean temperature and temperature of coldest quarter. These results indicate that climate is a strong driver of phenotypic divergence in Piranga bidentata.


Subject(s)
Passeriformes , Songbirds , Animals , Male , Female , Feathers/chemistry , Pigmentation/genetics , Songbirds/genetics , Passeriformes/genetics , Carotenoids/analysis
5.
Article in English | MEDLINE | ID: mdl-34639760

ABSTRACT

Child and adolescent sexual abuse (CSA) is an international public health problem. Despite the importance of CSA, there is no consensus definition, and the lack of consensus is related to difficulties in conducting prevalence studies as well as research in other areas. To establish a consensual definition, legal aspects such as the age of sexual consent and the difference in age or power between victim and aggressor as well as aspects related to sexual freedom and sexual indemnity must be considered. Therefore, the main goal of this research was to analyze the age of sexual consent in the legal systems of Spanish-speaking countries and to examine whether the Romeo and Juliet clause is established. To achieve the proposed aims, we employed the legal interpretation method, and we analyzed the current Criminal Codes of the 21 Spanish-speaking countries. From the results, it is found that the age of sexual consent varies between countries, establishing valid sexual consent between 13 and 18 years. In addition, only six countries have the Romeo and Juliet clause that protects sexual freedom in adolescents. Finally, we discussed the lack of consensus on the age of sexual consent and the limitations presented by the Romeo and Juliet clause.


Subject(s)
Child Abuse, Sexual , Criminals , Adolescent , Child , Freedom , Humans , Sexual Behavior
6.
Article in English | MEDLINE | ID: mdl-33920832

ABSTRACT

Sexual violence is a type of gender-based violence (GBV), as it is one of the different types of violence that is exerted against women. Sexual violence infringes fundamental human rights, and denies women's dignity and self-determination, personal development, and well-being. Despite international treaties and a regulatory framework that legally protects Colombian women against sexual violence, it is necessary to know the effectiveness of this regulatory framework in Colombia. Therefore, the main objective of this research is to examine criminal legislation on crimes of sexual violence in Colombia with a dual purpose: first, to analyze procedural guarantees for women victims of sexual violence; second, to determine obstacles for victims of sexual violence in accordance with the legal framework. We used a legal interpretation method to perform an analysis and interpret the law. The results found that, although sexual violence is considered a type of crime, procedural guarantees are not effective as victims encounter serious obstacles with negative consequences, such as the violation of fundamental human rights.


Subject(s)
Crime Victims , Sex Offenses , Colombia , Crime , Female , Human Rights , Humans , Sex Offenses/prevention & control , Violence , Women's Rights
7.
Zookeys ; 952: 129-157, 2020.
Article in English | MEDLINE | ID: mdl-32774114

ABSTRACT

The integration of genetic, morphological, behavioral, and ecological information in the analysis of species boundaries has increased, allowing integrative systematics that better reflect the evolutionary history of biological groups. In this context, the goal of this study was to recognize independent evolutionary lineages within Euphonia affinis at the genetic, morphological, and ecological levels. Three subspecies have been described: E. affinis godmani, distributed in the Pacific slope from southern Sonora to Guerrero; E. affinis affinis, from Oaxaca, Chiapas and the Yucatan Peninsula to Costa Rica; and E. affinis olmecorum from Tamaulipas and San Luis Potosi east to northern Chiapas (not recognized by some authors). A multilocus analysis was performed using mitochondrial and nuclear genes. These analyses suggest two genetic lineages: E. godmani and E. affinis, which diverged between 1.34 and 4.3 My, a period in which the ice ages and global cooling fragmented the tropical forests throughout the Neotropics. To analyze morphometric variations, six morphometric measurements were taken, and the Wilcoxon Test was applied to look for sexual dimorphism and differences between the lineages. Behavioral information was included, by performing vocalization analysis which showed significant differences in the temporal characteristics of calls. Finally, Ecological Niche Models were estimated with MaxEnt, and then compared using the method of Broennimann. These analyses showed that the lineage distributed in western Mexico (E. godmani) has a more restricted niche than the eastern lineage (E. affinis) and thus we rejected the hypotheses of niche equivalence and similarity. Based on the combined evidence from genetic, morphological, behavioral, and ecological data, it is concluded that E. affinis (with E. olmecorum as its synonym) and E. godmani represent two independent evolutionary lineages.

8.
Ecol Evol ; 9(21): 12339-12352, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31832165

ABSTRACT

AIM: The effects of geographic and environmental variables on patterns of genetic and phenotypic differentiation have been thoroughly studied. Ecological speciation involves reproductive isolation due to divergent natural selection that can result in a positive correlation between genetic divergence and adaptive phenotypic divergence (isolation by adaptation, IBA). If the phenotypic target of selection is unknown or not easily measured, environmental variation can be used as a proxy, expecting positive correlation between genetic and environmental distances, independent of geographic distances (isolation by environment, IBE). The null model is that the amount of gene flow between populations decreases as the geographic distance between them increases, and genetic divergence is due simply to the neutral effects of genetic drift (isolation by distance, IBD). However, since phenotypic differentiation in natural populations may be autocorrelated with geographic distance, it is often difficult to distinguish IBA from the neutral expectation of IBD. In this work, we test hypotheses of IBA, IBE, and IBD in the Red-crowned Ant tanager (Habia rubica). LOCATION: Mesoamerica (Mexico-Central America) and South America. TAXON: Habia rubica (Aves: Cardinalidae). METHODS: We compiled genetic data, coloration, and morphometric data from specimens from collections in Mexico and the United States. We used the Multiple Matrix Regression with Randomization (MMRR) approach to evaluate the influence of geographic and environmental distances on genetic and phenotypic differentiation of H. rubica at both phylogroup and population levels. RESULTS: Our results provide strong evidence that geographic distance is the main driver of genetic variation in H. rubica. We did not find evidence that climate variation is driving population differentiation in this species across a widespread geographic region. MAIN CONCLUSIONS: Our data point to geographic isolation as the main factor structuring genetic variation within populations of H. rubica and suggest that climate is not playing a major role in genetic differentiation within this species.

9.
PeerJ ; 6: e5496, 2018.
Article in English | MEDLINE | ID: mdl-30225165

ABSTRACT

Many neotropical species have a complex history of diversification as a result of the influence of geographical, ecological, climatic, and geological factors that determine the distribution of populations within a lineage. Phylogeography identifies such populations, determines their geographic distributions, and quantifies the degree of genetic divergence. In this work we explored the genetic structure of Habia rubica populations, a polytypic taxon with 17 subspecies described, in order to obtain hypotheses about their evolutionary history and processes of diversification. We undertook multilocus analyses using sequences of five molecular markers (ND2, ACOI-I9, MUSK, FGB-I5 and ODC), and sampling from across the species' distribution range, an area encompassing from Central Mexico throughout much of South America. With these data, we obtained a robust phylogenetic hypothesis, a species delimitation analysis, and estimates of divergence times for these lineages. The phylogenetic hypothesis of concatenated molecular markers shows that H. rubica can be divided in three main clades: the first includes Mexican Pacific coast populations, the second is formed by population from east of Mexico to Panama and the third comprises the South American populations. Within these clades we recognize seven principal phylogroups whose limits have a clear correspondence with important geographical discontinuities including the Isthmus of Tehuantepec in southern Mexico, the Talamanca Cordillera, and the Isthmus of Panama in North America. In South America, we observed a marked separation of two phylogroups that include the populations that inhabit mesic forests in western and central South America (Amazon Forest) and those inhabiting the seasonal forest from the eastern and northern regions of the South America (Atlantic Forest). These areas are separated by an intervening dry vegetation "diagonal" (Chaco, Cerrado and Caatinga). The geographic and genetic structure of these phylogroups describes a history of diversification more active and complex in the northern distribution of this species, producing at least seven well-supported lineages that could be considered species.

10.
Front Physiol ; 9: 83, 2018.
Article in English | MEDLINE | ID: mdl-29563877

ABSTRACT

Preeclampsia is a maternal hypertensive disorder that affects up to 1 out of 12 pregnancies worldwide. It is characterized by proteinuria, endothelial dysfunction, and elevated levels of the soluble form of the vascular endothelial growth factor receptor-1 (VEGFR-1, known as sFlt-1). sFlt-1 effects are mediated in part by decreasing VEGF signaling. The direct effects of sFlt-1 on cellular metabolism and bioenergetics in preeclampsia, have not been established. The goal of this study was to evaluate whether sFlt-1 causes mitochondrial dysfunction leading to disruption of normal functioning in endothelial and placental cells in preeclampsia. Endothelial cells (ECs) and first-trimester trophoblast (HTR-8/SVneo) were treated with serum from preeclamptic women rich in sFlt-1 or with the recombinant protein. sFlt-1, dose-dependently inhibited ECs respiration and acidification rates indicating a metabolic phenotype switch enhancing glycolytic flux. HTR-8/SVneo displayed a strong basal glycolytic metabolism, remaining less sensitive to sFlt-1-induced mitochondrial impairment. Moreover, results obtained in ECs exposed to serum from preeclamptic subjects demonstrated that increased sFlt-1 leads to metabolic perturbations accountable for mitochondrial dysfunction observed in preeclampsia. sFlt-1 exacerbated mitochondrial reactive oxygen species (ROS) formation and mitochondrial membrane potential dissipation in ECs and trophoblasts exposed to serum from preeclamptic women. Forcing oxidative metabolism by culturing cells in galactose media, further sensitized cells to sFlt-1. This approach let us establish that sFlt-1 targets mitochondrial function in ECs. Effects of sFlt-1 on HTR-8/SVneo cells metabolism were amplified in galactose, demonstrating that sFlt-1 only target cells that rely mainly on oxidative metabolism. Together, our results establish the early metabolic perturbations induced by sFlt-1 and the resulting endothelial and mitochondrial dysfunction in preeclampsia.

11.
Trans R Soc Trop Med Hyg ; 106(11): 701-8, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22889571

ABSTRACT

Evidence on the comorbidity between soil-transmitted helminth infections and malaria is scarce and divergent. This study explored the interactions between soil-transmitted helminth infections and uncomplicated falciparum malaria in an endemic area of Colombia. A paired case-control study matched by sex, age and location in Tierralta, Cordoba, was done between January and September 2010. The incident cases were 68 patients with falciparum malaria and 178 asymptomatic controls. A questionnaire was used to gather information on sociodemographic variables. Additionally physical examinations were carried out, stool samples were analysed for intestinal parasites and blood samples for Ig E concentrations. We found associations between infection with hookworm (OR: 4.21; 95% CI: 1.68-11.31) and Ascaris lumbricoides (OR 0.43; 95% CI: 0.18-1.04) and the occurrence of falciparum malaria. The effects of soil-transmitted helminths on the occurrence of malaria were found to be paradoxical. While hookworm is a risk factor, A. lumbricoides has a protective effect. The findings suggest that, in addition to the comorbidity, the presence of common determinants of soil-transmitted helminth infections and malaria could also exist. While the biological mechanisms involved are not clear, public health policies aimed at the control of their common social and environmental determinants are suggested.


Subject(s)
Ascariasis/epidemiology , Helminthiasis/epidemiology , Hookworm Infections/epidemiology , Malaria, Falciparum/epidemiology , Trichuriasis/epidemiology , Adolescent , Adult , Animals , Ascariasis/microbiology , Case-Control Studies , Child , Child, Preschool , Colombia/epidemiology , Comorbidity , Feces/parasitology , Female , Helminthiasis/microbiology , Hookworm Infections/microbiology , Humans , Malaria, Falciparum/microbiology , Male , Middle Aged , Prevalence , Soil Microbiology , Surveys and Questionnaires , Trichuriasis/microbiology
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