Nicolas Ortiz-López

Dr. Nicolas Ortiz-López

University of Chile, Santiago, Región Metropolitana, Chile
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Journal Article
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AZAlejandra Zazueta
Alejandra Zazueta
Lucía Valenzuela-PérezLucía Valenzuela-Pérez
Lucía Valenzuela-Pérez
Nicolas Ortiz-LópezNicolas Ortiz-López
Nicolas Ortiz-López
AParaceli pinto
araceli pinto
VTVerónica Torres
Verónica Torres
CBCaroll Jenny Beltrán
Caroll Jenny Beltrán
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a complex disorder whose prevalence is rapidly growing in South America. The disturbances in the microbiota–gut–liver axis impact the liver damaging processes toward fibrosis. Gut microbiota status is shaped by dietary and lifestyle factors, depending on geographic location. We aimed to identify microbial signatures in a group of Chilean MASLD patients. Forty subjects were recruited, including healthy controls (HCs), overweight/obese subjects (Ow/Ob), patients with MASLD without fibrosis (MASLD/F−), and MASLD with fibrosis (MASLD/F+). Both MASLD and fibrosis were detected through elastography and/or biopsy, and fecal microbiota were analyzed through deep sequencing. Despite no differences in α- and β-diversity among all groups, a higher abundance of Bilophila and a lower presence of Defluviitaleaceae, Lachnospiraceae ND3007, and Coprobacter was found in MASLD/F− and MASLD/F+, compared to HC. Ruminococcaceae UCG-013 and Sellimonas were more abundant in MASLD/F+ than in Ow/Ob; both significantly differed between MASLD/F− and MASLD/F+, compared to HC. Significant positive correlations were observed between liver stiffness and Bifidobacterium, Prevotella, Sarcina, and Acidaminococcus abundance. Our results show that MASLD is associated with changes in bacterial taxa that are known to be involved in bile acid metabolism and SCFA production, with some of them being more specifically linked to fibrosis.

10 October 2022 in Frontiers in Immunology
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Nicolas Ortiz-LópezNicolas Ortiz-López
Nicolas Ortiz-López
CFCatalina Fuenzalida
Catalina Fuenzalida
MDMaría Soledad Dufeu
María Soledad Dufeu
APAraceli Pinto-León
Araceli Pinto-León
AEAlejandro Escobar
Alejandro Escobar
CBCaroll Jenny Beltrán
Caroll Jenny Beltrán
Non-alcoholic fatty liver disease (NAFLD) is a complex and heterogeneous disorder considered a liver-damaging manifestation of metabolic syndrome. Its prevalence has increased in the last decades due to modern-day lifestyle factors associated with overweight and obesity, making it a relevant public health problem worldwide. The clinical progression of NAFLD is associated with advanced forms of liver injury such as fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). As such, diverse pharmacological strategies have been implemented over the last few years, principally focused on metabolic pathways involved in NAFLD progression. However, a variable response rate has been observed in NAFLD patients, which is explained by the interindividual heterogeneity of susceptibility to liver damage. In this scenario, it is necessary to search for different therapeutic approaches. It is worth noting that chronic low-grade inflammation constitutes a central mechanism in the pathogenesis and progression of NAFLD, associated with abnormal composition of the intestinal microbiota, increased lymphocyte activation in the intestine and immune effector mechanisms in liver. This review aims to discuss the current knowledge about the role of the immune response in NAFLD development. We have focused mainly on the impact of altered gut-liver-microbiota axis communication on immune cell activation in the intestinal mucosa and the role of subsequent lymphocyte homing to the liver in NAFLD development. We further discuss novel clinical trials that addressed the control of the liver and intestinal immune response to complement current NAFLD therapies.

1 July 2021 in Revista médica de Chile
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Nicolas Ortiz-LópezNicolas Ortiz-López
Nicolas Ortiz-López
OJOscar Jerez-Yáñez
Oscar Jerez-Yáñez
FCFelipe Cortés-Chau
Felipe Cortés-Chau
JRJonathan Rodríguez-Cabello
Jonathan Rodríguez-Cabello
Particularmente, los estudiantes pertenecientes a la diversidad sexual y de género (DSG), es decir, la población lesbiana, gay, bisexual, transgénero/transexual y queer (LGBTQ+), experimentan estrés crónico debido a la estigmatización y la discriminación, lo que debilita su capacidad de centrarse en lo académico4 . Asimismo, en la educación superior existe cierta resistencia a la inclusión de la población LGBTQ+, la cual crea un clima que inhibe a muchas personas de ser abiertas sobre su orientación sexual o identidad de género5 . Este clima perpetúa que aquellos estudiantes continúen sintiéndose vulnerables y marginados5 , 6 .

24 May 2024 in Frontiers in Medicine
Verified
Journal Article
Open access
Nicolas Ortiz-LópezNicolas Ortiz-López
Nicolas Ortiz-López
AMAna María Madrid
Ana María Madrid
LALarissa Aleman
Larissa Aleman
AZAlejandra Zazueta
Alejandra Zazueta
GSGladys Smok
Gladys Smok
CBCaroll Jenny Beltrán
Caroll Jenny Beltrán
Background/aims: The metabolic dysfunction-associated steatotic liver disease (MASLD) and obesity are frequent comorbidities with a high prevalence worldwide. Their pathogenesis are multifactorial, including intestinal dysbiosis. The role of small intestinal bacterial overgrowth (SIBO) in MASLD progression in obese patients remains unknown. We aimed to determine the association between SIBO and the severity of MASLD in obese patients.Methods: An observational and cross-sectional study was conducted in obese patients, diagnosed with or without MASLD by liver biopsy. Metabolic dysfunction-associated steatotic liver (MASL), metabolic dysfunction-associated steatohepatitis without fibrosis (MASH-NF), MASH with fibrosis (MASH-F), or without MASLD (control subjects, CS) were identified by presence of steatosis, portal and lobular inflammation, and fibrosis. SIBO was determined by standardized lactulose breath tests.Results: A total of 59 patients with MASLD, 16 with MASL, 20 with MASH-NF, 23 with MASH-F, and 14 CS were recruited. Higher percentages of SIBO were observed in MASLD patients (44.2%) compared to CS (14.2%; p = 0.0363). Interestingly, MASH-F showed higher percentages of SIBO (65.2%) in comparison to non-fibrotic MASLD (33.3%; p = 0.0165). The presence of SIBO was not correlated with the level of hepatic steatosis in MASLD patients.Conclusions: A positive correlation between MASLD and SIBO in obese patients was principally explained by the presence of liver fibrosis. Our findings suggest a pathogenic role of intestinal dysbiosis in the progression of MASLD. Future research will elucidate the underlying mechanisms of SIBO in MASLD advancement.

21 February 2024 in BMC Medical Education
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Journal Article
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MRMarcos Rojas
Marcos Rojas
JGJoaquín Cánepa González
Joaquín Cánepa González
Nicolas Ortiz-LópezNicolas Ortiz-López
Nicolas Ortiz-López
Background: Lesbian, gay, bisexual, transgender, intersex, queer, and other sexual and gender identities (LGBTIQ+) individuals face health inequities. Additionally, medical students report a lack of confidence in providing specific health care to LGBTIQ + individuals, and medical schools do not offer the breadth and depth of coverage needed to fully prepare and make them comfortable in caring for these individuals. This study aims to characterize the teaching of curricular content related to LGBTIQ + health issues in medical schools in Chile. Methods: This was a cross-sectional descriptive mixed-methods study based on a 15-question survey sent to school directors of the 24 medical schools in Chile, conducted between October 2020 and July 2021. The questions included in the study were mostly based on two pre-existing questionnaires covering content, assessment methods, and identification of barriers to teaching this content. Results: The validated questionnaire was answered by 14 of 24 Chilean medical schools, with 11 schools (78.9%) declaring that they included some training in their curriculum. The predominant range of time allocated to LGBTIQ + training in medical programs was between 1 and 5 h. The most addressed topics were HIV (92.85%), sexual orientation (78.57%), and chronic disease risk in LGBTIQ + populations (78.57%). Most schools, accounting for 71.5%, considered the content they delivered to be “moderately insufficient” or “insufficient”. Regarding the teaching methodologies, the most used were lectures (92.8%), clinical cases (42.9%), and clinical simulation (28.6%). Conclusion: Most surveyed medical schools reported curricular spaces dedicated to teaching health issues of LGBTIQ + individuals, primarily during the pre-internship training period. However, the time allocated is insufficient, and there is little approach to topics beyond the patient’s sexual history or sexual orientation. Given the crucial role of medical schools, they must adopt both local and national strategies to enrich training focused on the care of LGBTIQ + patients.

1 October 2024 in Revista médica de Chile
Verified
Journal Article
Closed access
Nicolas Ortiz-LópezNicolas Ortiz-López
Nicolas Ortiz-López
SPSofía Ponce-Arancibia
Sofía Ponce-Arancibia
LALarissa Aleman
Larissa Aleman
JRJuan Pablo Roblero
Juan Pablo Roblero
ÁUÁlvaro Urzúa
Álvaro Urzúa
JPJaime Poniachik
Jaime Poniachik
Chronic liver disease (CLD) is one of the leading causes of morbidity and mortality in Chile. The progression of the disease generally involves a prolonged asymptomatic phase, during which there is an opportunity for early diagnosis and interventions to prevent progression to advanced disease and its complications. Although risk factors are well-characterized today, and access to diagnostic tests has significantly improved, CLD is not yet included in long-term condition management programs in primary health care (PHC). In this context, it is essential for PHC to focus on primary prevention and early detection of liver diseases, aiming to reduce the socio-health burden of liver cirrhosis, and prevent its progression to decompensated cirrhosis, end-stage liver disease, and hepatocellular carcinoma. To define the initial management of chronic liver diseases in adults in primary care. narrative review. We provide an overview of the initial management of chronic liver diseases in adults in PHC, including aspects focused on prevention, identification of patients with liver disease, appropriate application of diagnostic tests, delivery of proper counseling, and timely referrals to specialists.