CRIS

Permanent URI for this communityhttps://investigadores.udd.cl/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 11

Some of the metrics are blocked by your
consent settings
Geographic divergence of methicillin-resistant Staphylococcus aureus ST5-SCCmecI in the aftermath of a major earthquake and tsunami: impact of a plasmid harboring heavy metal resistance genes
(American Society for Microbiology, 2025-04-09)
Jose R. W. Martínez
;
Manuel Alcalde-Rico
;
Estefanía Jara-Videla
;
Jinnethe Reyes
;
Lina P. Carvajal
(MRSA) is a major public health menace. The global spread of MRSA is characterized by successive waves of epidemic clones dominating specific geographical regions. The acquisition of genes encoding resistance to heavy metals (HMRGs) is thought to be a key feature in the geographic divergence of MRSA. However, the cause-effect relationship between the presence of HMRGs and the divergence of MRSA clones remains to be clarified. In this study, we assessed the role that HMRGs may have played in the evolutionary divergence of the MRSA ST5-SCC <jats:italic>mec</jats:italic> I lineage in Latin America. We conducted a genomic characterization of 113 MRSA clinical isolates from six Latin American healthcare centers, including 53 isolates collected from two cities in Chile (Santiago and Concepción). We found a plasmid (pSCL4752) harboring arsenic, cadmium, and mercury resistance genes in 65% ( <jats:italic>n</jats:italic> = 71) of the ST5-SCC <jats:italic>mec</jats:italic> I isolates. We also observed a geographic divergence associated with the presence of pSCL4752 in Chilean isolates, with a higher frequency in isolates from Concepción (88%) compared to Santiago (29%). Interestingly, a molecular clock analysis revealed that this divergence occurred in the aftermath of an 8.8 Mw earthquake and tsunami that struck the Concepción area in 2010. Moreover, our results demonstrate that the carriage of pSCL4752 can be beneficial or detrimental for ST5-SCC <jats:italic>mec</jats:italic> I isolates, depending on the environmental availability of these heavy metals. Our results suggest that the divergence of the ST5-SCC <jats:italic>mec</jats:italic> I MRSA lineage in Latin America could have been fostered by environmental disasters and influenced by the presence/absence of HMRGs harbored in a plasmid. </jats:p> <jats:sec> <jats:title>IMPORTANCE</jats:title> <jats:p> Methicillin-resistant <jats:italic>Staphylococcus aureus</jats:italic> (MRSA) is a major cause of life-threatening infections worldwide and a growing public health concern. The rise of antibiotic-resistant bacteria, such as MRSA, is often linked to genetic adaptations that enhance their survival. Our research sheds light on how environmental changes, such as those triggered by a natural disaster, can influence the evolution and geographic spread of a highly resistant MRSA lineage in Latin America. We identified a plasmid carrying genes for resistance to arsenic, cadmium, and mercury, which was associated with the geographic divergence of the ST5-SCC <jats:italic>mec</jats:italic> I MRSA lineage, with striking differences in its prevalence between regions affected by a major earthquake and tsunami. By linking environmental events to pathogen evolution, our study highlights the role of ecological pressures in the spread of MRSA. These findings emphasize the need to integrate environmental monitoring into public health strategies to better understand the global challenge of antimicrobial resistance.
4
Some of the metrics are blocked by your
consent settings
Low-cost screening method for estimating inorganic arsenic in soil
(Springer Science and Business Media LLC, 2025-02-19)
Dan Walls
;
Rodríguez María Delia
;
Robert A. Root
;
God’sgift N. Chukwuonye
;
Zain Alabdain Alqattan
10
Some of the metrics are blocked by your
consent settings
Arsenic Exposure During Pregnancy and Childhood: Factors Explaining Changes over a Decade
(MDPI AG, 2025-03-16)
RUBILAR RAMIREZ, PAOLA ANDREA
;
HIRMAS ADAUY, MACARENA SOLEDAD
;
APABLAZA SALINAS, MAURICIO IVÁN
;
Camila Awad
;
Xaviera Molina
Arsenic chronic exposure, particularly in its inorganic form, represents a significant public health concern. This study was conducted in Arica, the northernmost city in the country, whose inhabitants have been exposed to inorganic arsenic both naturally through drinking water and anthropogenically due to a toxic waste disposal site. We explored changes in inorganic arsenic levels in a cohort of pregnant women and their children over a decade, identifying exposure trends and their determinants. We used data on arsenic exposure through maternal urine samples during pregnancy, collected by the Health Authority between 2013 and 2016 (measurement 1), and followed up with assessments of their children in 2023 (measurement 2). Temporal changes in inorganic arsenic concentration were analyzed using the Wilcoxon Signed-Rank test, and a mixed linear regression model was employed to determine which factors contributed to urinary inorganic arsenic levels. We did not observe significant differences in mean arsenic concentrations between the two-time points (p = 0.4026). The mixed linear regression model revealed that children consuming bottled water had 8.3% lower urinary inorganic arsenic concentrations than those drinking tap water (95% CI: −15.36 to −0.54%). Additionally, children from ethnic groups had 8.64% higher inorganic arsenic concentrations (95% CI: 0.49 to 17.5%), while those with caregivers with higher education showed a 13.67% reduction (95% CI: −25.06 to −0.56%). Despite mitigation efforts, these findings underscore the ongoing risk of inorganic arsenic exposure among vulnerable populations. They further emphasize the importance of addressing natural arsenic contamination in water and implementing targeted interventions to reduce disparities associated with socioeconomic and demographic factors.</jats:p>
Scopus© Citations 1 6
Some of the metrics are blocked by your
consent settings
A Systematic Literature Review on the Use of Clays for Arsenic Removal
(MDPI AG, 2025-05-07)
Lorenzo Reyes-Bozo
;
Eduardo Vyhmeister
;
Gabriel G. Castane
;
Juan Chirinos
;
Jeannette Zárraga
Arsenic contamination in water remains a critical global challenge, particularly in rural and resource-limited regions. Clays have been widely studied as cost-effective and efficient adsorbents for arsenic removal. This systematic review provides a comprehensive analysis of the application of clays in arsenic adsorption, focusing on clay types, operational units, and study methodologies. The review classifies the adsorption mechanisms, highlights key factors influencing adsorption performance—such as pH, ionic strength, and surface modifications—and examines the effectiveness of various modifications. Furthermore, the study categorizes adsorption research into kinetic, iso-thermal, thermodynamic, and efficiency studies, providing insights into the state of the art and the experimental conditions that govern arsenic removal. It also discusses the scalability and practical application of clay-based adsorption technologies, emphasizing gaps in field validation, regeneration studies, and large-scale implementation. The findings highlight the potential of natural and modified clays in arsenic remediation, while underscoring the need for further research to optimize adsorption conditions and enhance sustainability in water treatment systems.
2
Some of the metrics are blocked by your
consent settings
Arsenic exposure is associated with significant upper tract urothelial carcinoma health care needs and elevated mortality rates
(Elsevier BV, 2020-07)
José Francisco López
;
FERNANDEZ ARANCIBIA, MARIO
;
Luis Fernando Coz
Scopus© Citations 7 2
Some of the metrics are blocked by your
consent settings
Circulating arsenic is associated with long-term risk of graft failure in kidney transplant recipients: A prospective cohort study
(2023-06-23)
Sotomayor, Camilo G.
;
Groothof, Dion
;
Vodegel, Joppe J.
;
Gacitúa, Tomás A.
;
Gomes-Neto, António W.
12
Some of the metrics are blocked by your
consent settings
Attention deficit hyperactivity disorder and its association with heavy metals in children from northern Chile
(2020)
María Pía Muñoz
;
RUBILAR RAMIREZ, PAOLA
;
Macarena Valdés
;
María Teresa Muñoz-Quezada
;
Andrea Gómez
5Scopus© Citations 38
Some of the metrics are blocked by your
consent settings
Adsorption of As (V) by poly (N-octyl-4-vinylpyridinium) bromide: Determination of As (V) by direct measurement of fluorescence on the solid phase
(2016)
Javier González-Navarrete
;
María Inés Toral
;
Angel Leiva
;
Mehrdad Yazdani-Pedram
;
Hernán E. Ríos
17Scopus© Citations 5
Some of the metrics are blocked by your
consent settings
Adaptation to Extreme Environments in an Admixed Human Population from the Atacama Desert
(2019)
Lucas Vicuña
;
FERNANDEZ ARANCIBIA, MARIO
;
VIAL COX, MARIA CECILIA
;
Patricio Valdebenito
;
Eduardo Chaparro
<jats:title>Abstract</jats:title><jats:p>Inorganic arsenic (As) is a toxic xenobiotic and carcinogen associated with severe health conditions. The urban population from the Atacama Desert in northern Chile was exposed to extremely high As levels (up to 600 µg/l) in drinking water between 1958 and 1971, leading to increased incidence of urinary bladder cancer (BC), skin cancer, kidney cancer, and coronary thrombosis decades later. Besides, the Andean Native-American ancestors of the Atacama population were previously exposed for millennia to elevated As levels in water (∼120 µg/l) for at least 5,000 years, suggesting adaptation to this selective pressure. Here, we performed two genome-wide selection tests—PBSn1 and an ancestry-enrichment test—in an admixed population from Atacama, to identify adaptation signatures to As exposure acquired before and after admixture with Europeans, respectively. The top second variant selected by PBSn1 was associated with LCE4A-C1orf68, a gene that may be involved in the immune barrier of the epithelium during BC. We performed association tests between the top PBSn1 hits and BC occurrence in our population. The strongest association (P = 0.012) was achieved by the LCE4A-C1orf68 variant. The ancestry-enrichment test detected highly significant signals (P = 1.3 × 10−9) mapping MAK16, a gene with important roles in ribosome biogenesis during the G1 phase of the cell cycle. Our results contribute to a better understanding of the genetic factors involved in adaptation to the pathophysiological consequences of As exposure.</jats:p>
Scopus© Citations 15 1
Some of the metrics are blocked by your
consent settings
Impact of arsenic exposure on clinicopathological characteristics of bladder cancer: A comparative study between patients from an arsenic-exposed region and nonexposed reference sites
(2020)
FERNANDEZ ARANCIBIA, MARIO
;
Patricio Valdebenito
;
DELGADO BECERRA, OROZIMBA IRIS
;
Jorge Segebre
;
Eduardo Chaparro
Scopus© Citations 10 1 3

CRIS

Browse

Filters

Settings

Sort By

Results per page

Search Results