Browsing by Author "Castillo, Andres"

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    Cross-species and mammal-to-mammal transmission of clade 2.3.4.4b highly pathogenic avian influenza A/H5N1 with PB2 adaptations
    (2025) Pardo Roa, Catalina; Nelson, Martha I.; Ariyama, Naomi; Aguayo, Carolina; Almonacid Cárdenas, Leonardo Iván; Gonzalez-Reiche, Ana S.; Muñoz, Gabriela; Ulloa, Mauricio; Avila, Claudia; Navarro, Carlos; Reyes, Rodolfo; Castillo Torres, Pablo Nicolás; Mathieu, Christian; Vergara, Ricardo; Gonzalez, Alvaro; Gonzalez, Carmen Gloria; Araya, Hugo; Castillo, Andres; Torres, Juan Carlos; Covarrubias, Paulo; Bustos, Patricia; van Bakel, Harm; Fernandez, Jorge; Fasce, Rodrigo A.; Johow, Magdalena; Neira, Victor; Medina, Rafael
    Highly pathogenic H5N1 avian influenza viruses (HPAIV) belonging to lineage 2.3.4.4b emerged in Chile in December 2022, leading to mass mortality events in wild birds, poultry, and marine mammals and one human case. We detected HPAIV in 7,33% (714/9745) of cases between December 2022-April 2023 and sequenced 177 H5N1 virus genomes from poultry, marine mammals, a human, and wild birds spanning >3800 km of Chilean coastline. Chilean viruses were closely related to Peru's H5N1 outbreak, consistent with north-to-south spread down the Pacific coastline. One human virus and nine marine mammal viruses in Chile had the rare PB2 D701N mammalian-adaptation mutation and clustered phylogenetically despite being sampled 5 weeks and hundreds of kilometers apart. These viruses shared additional genetic signatures, including another mammalian PB2 adaptation (Q591K, n = 6), synonymous mutations, and minor variants. Several mutations were detected months later in sealions in the Atlantic coast, indicating that the pinniped outbreaks on the west and east coasts of South America are genetically linked. These data support sustained mammal-to-mammal transmission of HPAIV in marine mammals over thousands of kilometers of Chile's Pacific coastline, which subsequently continued through the Atlantic coastline.
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    Cross-species and mammal-to-mammal transmission of clade 2.3.4.4b highly pathogenic avian influenza A/H5N1 with PB2 adaptations
    (2025) Pardo Roa, Catalina; Nelson, Martha I.; Ariyama, Naomi; Aguayo, Carolina; Almonacid Cárdenas, Leonardo Iván; Gonzalez-Reiche, Ana S.; Muñoz, Gabriela; Ulloa, Mauricio; Avila, Claudia; Navarro, Carlos; Reyes, Rodolfo; Castillo Torres, Pablo Nicolás; Mathieu, Christian; Vergara, Ricardo; Gonzalez, Alvaro; Gonzalez, Carmen Gloria; Araya, Hugo; Castillo, Andres; Torres, Juan Carlos; Covarrubias, Paulo; Bustos, Patricia; van Bakel, Harm; Fernandez, Jorge; Fasce, Rodrigo A.; Johow, Magdalena; Neira, Victor; Medina, Rafael
    Highly pathogenic H5N1 avian influenza viruses (HPAIV) belonging to lineage 2.3.4.4b emerged in Chile in December 2022, leading to mass mortality events in wild birds, poultry, and marine mammals and one human case. We detected HPAIV in 7,33% (714/9745) of cases between December 2022-April 2023 and sequenced 177 H5N1 virus genomes from poultry, marine mammals, a human, and wild birds spanning >3800 km of Chilean coastline. Chilean viruses were closely related to Peru's H5N1 outbreak, consistent with north-to-south spread down the Pacific coastline. One human virus and nine marine mammal viruses in Chile had the rare PB2 D701N mammalian-adaptation mutation and clustered phylogenetically despite being sampled 5 weeks and hundreds of kilometers apart. These viruses shared additional genetic signatures, including another mammalian PB2 adaptation (Q591K, n = 6), synonymous mutations, and minor variants. Several mutations were detected months later in sealions in the Atlantic coast, indicating that the pinniped outbreaks on the west and east coasts of South America are genetically linked. These data support sustained mammal-to-mammal transmission of HPAIV in marine mammals over thousands of kilometers of Chile's Pacific coastline, which subsequently continued through the Atlantic coastline.
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    Epstein-Barr Virus BARF1 Is Expressed in Lung Cancer and Is Associated with Cancer Progression
    (2024) Osorio, Julio C.; Armijo, Alvaro; Carvajal, Francisco J.; Corvalan, Alejandro H.; Castillo, Andres; Fuentes-Panana, Ezequiel M.; Moreno-Leon, Carolina; Romero, Carmen; Aguayo, Francisco
    Background: Epstein-Barr virus (EBV) is involved in the development of lymphomas, nasopharyngeal carcinomas (NPC), and a subgroup of gastric carcinomas (GC), and has also been detected in lung carcinomas, even though the role of the virus in this malignancy has not yet been established. BamH1-A Rightward Frame 1 (BARF1), a suggested exclusive epithelial EBV oncoprotein, is detected in both EBV-associated GCs (EBVaGC) and NPC. The expression and role of BARF1 in lung cancer is unknown. Methods: A total of 158 lung carcinomas including 80 adenocarcinomas (AdCs) and 78 squamous cell carcinomas (SQCs) from Chilean patients were analyzed for EBV presence via polymerase chain reaction (PCR), Immunohistochemistry (IHC), or chromogenic in situ hybridization (CISH). The expression of BARF1 was evaluated using Reverse Transcription Real-Time PCR (RT-qPCR). Additionally, A549 and BEAS-2B lung epithelial cells were transfected with a construct for ectopic BARF1 expression. Cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) were evaluated. Results: We found that EBV was present in 37 out of 158 (23%) lung carcinomas using PCR. Considering EBV-positive specimens using PCR, IHC for Epstein-Barr nuclear antigen 1 (EBNA1) detected EBV in 24 out of 30 (80%) cases, while EBERs were detected using CISH in 13 out of 16 (81%) cases. Overall, 13 out of 158 (8%) lung carcinomas were shown to be EBV-positive using PCR/IHC/CISH. BARF1 transcripts were detected in 6 out of 13 (46%) EBV-positive lung carcinomas using RT qPCR. Finally, lung cells ectopically expressing BARF1 showed increased migration, invasion, and EMT. Conclusions. EBV is frequently found in lung carcinomas from Chile with the expression of BARF1 in a significant subset of cases, suggesting that this viral protein may be involved in EBV-associated lung cancer progression.
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    Human papillomavirus in esophageal squamous cell carcinoma in Colombia and Chile
    (W J G PRESS, 2006) Castillo, Andres; Aguayo, Francisco; Koriyama, Chihaya; Torres, Miyerlandi; Carrascal, Edwin; Corvalan, Alejandro; Roblero, Juan P.; Naquira, Cecilia; Palma, Mariana; Backhouse, Claudia; Argandona, Jorge; Itoh, Tetsuhiko; Shuyama, Karem; Eizuru, Yoshito; Akiba, Suminori
    AIM: To examine the presence of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) specimens collected from Colombia and Chile located in the northern and southern ends of the continent, respectively.