Browsing by Autor "Gabriela Morales"

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Concentrations and stable isotopes of mercury in sharks of the Galapagos Marine Reserve: Human health concerns and feeding patterns
(2021) Laurence Maurice; Gaël Le Croizier; Gabriela Morales; Natalia Carpintero; Juan M. Guayasamin; Jeroen E. Sonke; Diego Páez‐Rosas; David Point; Walter Bustos; Valeria Ochoa‐Herrera
The human ingestion of mercury (Hg) from sea food is of big concern worldwide due to adverse health effects, and more specifically if shark consumption constitutes a regular part of the human diet. In this study, the total mercury (THg) concentration in muscle tissue were determined in six sympatric shark species found in a fishing vessel seized in the Galapagos Marine Reserve in 2017. The THg concentrations in shark muscle samples (n = 73) varied from 0.73 mg kg-1 in bigeye thresher sharks (Alopias superciliosus) to 8.29 mg kg-1 in silky sharks (Carcharhinus falciformis). A typical pattern of Hg bioaccumulation was observed for all shark species, with significant correlation between THg concentration and shark size for bigeye thresher sharks, pelagic thresher sharks (Alopias pelagicus) and silky sharks. Regarding human health concerns, the THg mean concentration exceeded the maximum weekly intake fish serving in all the studied species. Mass-Dependent Fractionation (MDF, δ202Hg values) and Mass-Independent Fractionation (MIF, Δ199Hg values) of Hg in whitetip sharks (Carcharhinus longimanus) and silky sharks, ranged from 0.70‰ to 1.08‰, and from 1.97‰ to 2.89‰, respectively. These high values suggest that both species are feeding in the epipelagic zone (i.e. upper 200 m of the water column). While, blue sharks (Prionace glauca), scalloped hammerhead sharks (Shyrna lewini) and thresher sharks were characterized by lower Δ199Hg and δ202Hg values, indicating that these species may focus their foraging behavior on prey of mesopelagic zone (i.e. between 200 and 1000 m depth). In conclusion, the determination of THg concentration provides straight-forward evidence of the human health risks associated with shark consumption, while mercury isotopic compositions constitute a powerful tool to trace the foraging strategies of these marine predators. CAPSULE: A double approach combining Hg concentrations with stable isotopes ratios allowed to assess ontogeny in common shark species in the area of the Galapagos Marine Reserve and the human health risks concern associated to their consumption.
Determination of the Microbial and Chemical Loads in Rivers from the Quito Capital Province of Ecuador (Pichincha)—A Preliminary Analysis of Microbial and Chemical Quality of the Main Rivers
(Multidisciplinary Digital Publishing Institute, 2020) Pamela Borja-Serrano; Valeria Ochoa‐Herrera; Laurence Maurice; Gabriela Morales; Cristian Quilumbaqui; Eduardo Tejera; António Machado
Contamination of natural water sources is one of the main health problems worldwide, which could be caused by chemicals, metals, or microbial agents. This study aimed to analyze the quality of 18 rivers located in Quito, the capital province of Pichincha, Ecuador, through physico-chemical and microbial parameters. The E. coli and total coliforms assessments were performed by a counting procedure in growth media. Polymerase chain reaction (PCR) was realized to detect several microbial genera, as well as Candida albicans, two parasites (Cryptosporidium and Giardia spp.) and E. coli pathotypes: enterohemorrhagic E. coli (EHEC), enteroaggregative E. coli (EAEC), enteroinvasive E. coli (EIEC) and enteropathogenic E. coli (EPEC). Additionally, physico-chemical parameters and major and trace metals were analyzed in each surface water sample. Our results demonstrated that most of the rivers analyzed do not comply with the microbial, physico-chemical, and metal requirements established by the Ecuadorian legislation. In terms of microbial pollution, the most polluted rivers were Monjas, Machángara, Pisque, and Pita Rivers. Furthermore, three out of four analyzed E. coli pathotypes (EIEC, EHEC, and EAEC) were detected in certain rivers, specifically: Monjas River showed the presence of EIEC and EHEC; in the Machángara River, EAEC and EIEC were detected; and finally, EIEC was present in the Guayllabamba River. Several physico-chemical parameters, such as pH, CODtotal, and TSS values, were higher than the Ecuadorian guidelines in 11, 28, and 28% of the rivers, respectively. Regarding heavy metals, Zn, Cu, Ni, Pb, Cd, and Mn surpassed the established values in 94, 89, 61, 22, 22, and 17% of the rivers, respectively. Machangara River was the only one that registered higher Cr concentrations than the national guidelines. The values of Al and Fe were above the recommended values in 83 and 72% of the rivers. Overall, based on the physical-chemical and microbiological parameters the most contaminated rivers were Machángara and Monjas. This study revealed severe contaminations in Ecuadorean Rivers; further studies should evaluate the sources of contamination and their impact on public health.
Sexuality and Well-Being Among Community-Dwelling Older Adults in Bogotá, Colombia
(University of Oxford, 2025) Maria Fernanda F. Reyes; Natalie Levy; M Castro; Gabriela Morales; Gabriela Garcia; Maria Ordoñez; Angie Riveros
Abstract Sexuality in late life is often overlooked, yet it plays a significant role in the well-being and mental health of older adults. We conducted a mixed methods study to explore the relationship between sexuality, well-being, and psychosocial factors among older adults in Bogotá, Colombia. The quantitative phase included 615 older adults (Mage= 66), 57.3% women, 40.9% men, and 1.4% transwomen. Surveys measured sexual well-being, depression, resilience, life satisfaction, and social support. The qualitative phase involved interviews with 19 participants (7 women, 6 men, and 6 transwomen), exploring experiences of sexuality, intimacy, and interactions with healthcare providers. Results multiple linear regression analysis showed that overall sexual satisfaction was predicted by age and awareness of the right to a fulfilling sexual life. Significant correlations were found between higher satisfaction with social support and perceived sexual compatibility and overall sexual satisfaction. Low social support was associated with higher distress in sexual functioning. Qualitative findings highlighted stigma surrounding aging and sexuality, particularly among transgender individuals. Participants highlighted the continued relevance of sexuality, especially for those in active relationships. While some saw no changes with aging, most reported significant shifts. Participants revealed that professionals rarely addressed sexuality. Discussion social support, awareness of sexual rights, and resilience were positively associated with higher sexual satisfaction. Participants recognized changes in their sexuality as they aged. Cultural and religious beliefs played a crucial role in discussing sexuality, as many participants initially felt barriers to speaking openly. However, they acknowledged that sexuality is an important yet hidden topic.
Sexuality and Well-Being Among Community-Dwelling Older Adults in Bogotá, Colombia
(University of Oxford, 2025) Maria Fernanda F. Reyes; Natalie Levy; M Castro; Gabriela Morales; Gabriela Garcia; Maria Ordoñez; Angie Riveros
Abstract Sexuality in late life is often overlooked, yet it plays a significant role in the well-being and mental health of older adults. We conducted a mixed methods study to explore the relationship between sexuality, well-being, and psychosocial factors among older adults in Bogotá, Colombia. The quantitative phase included 615 older adults (Mage= 66), 57.3% women, 40.9% men, and 1.4% transwomen. Surveys measured sexual well-being, depression, resilience, life satisfaction, and social support. The qualitative phase involved interviews with 19 participants (7 women, 6 men, and 6 transwomen), exploring experiences of sexuality, intimacy, and interactions with healthcare providers. Results multiple linear regression analysis showed that overall sexual satisfaction was predicted by age and awareness of the right to a fulfilling sexual life. Significant correlations were found between higher satisfaction with social support and perceived sexual compatibility and overall sexual satisfaction. Low social support was associated with higher distress in sexual functioning. Qualitative findings highlighted stigma surrounding aging and sexuality, particularly among transgender individuals. Participants highlighted the continued relevance of sexuality, especially for those in active relationships. While some saw no changes with aging, most reported significant shifts. Participants revealed that professionals rarely addressed sexuality. Discussion social support, awareness of sexual rights, and resilience were positively associated with higher sexual satisfaction. Participants recognized changes in their sexuality as they aged. Cultural and religious beliefs played a crucial role in discussing sexuality, as many participants initially felt barriers to speaking openly. However, they acknowledged that sexuality is an important yet hidden topic.