Eva Megumi Nara

Dr. Eva Megumi Nara

Instituto de Investigaciones en Ciencias de la Salud, San Lorenzo, Central, Paraguay
orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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11 February 2022 in Interface Focus
Verified
Journal Article
Open access
JTJulian Tang
Julian Tang
MCMiguela A. Caniza
Miguela A. Caniza
MDMike Dinn
Mike Dinn
DDDominic E. Dwyer
Dominic E. Dwyer
Jean-Michel HeraudJean-Michel Heraud
Jean-Michel Heraud
SZSabeen Khurshid Zaidi
Sabeen Khurshid Zaidi
Responses to the early (February–July 2020) COVID-19 pandemic varied widely, globally. Reasons for this are multiple but likely relate to the healthcare and financial resources then available, and the degree of trust in, and economic support provided by, national governments. Cultural factors also affected how different populations reacted to the various pandemic restrictions, like masking, social distancing and self-isolation or self-quarantine. The degree of compliance with these measures depended on how much individuals valued their needs and liberties over those of their society. Thus, several themes may be relevant when comparing pandemic responses across different regions. East and Southeast Asian populations tended to be more collectivist and self-sacrificing, responding quickly to early signs of the pandemic and readily complied with most restrictions to control its spread. Australasian, Eastern European, Scandinavian, some Middle Eastern, African and South American countries also responded promptly by imposing restrictions of varying severity, due to concerns for their wider society, including for some, the fragility of their healthcare systems. Western European and North American countries, with well-resourced healthcare systems, initially reacted more slowly, partly in an effort to maintain their economies but also to delay imposing pandemic restrictions that limited the personal freedoms of their citizens.

22 April 2022 in Viruses
Verified
Journal Article
Open access
PDF file
MMMagaly Martinez
Magaly Martinez
PNPhuong-Vi Nguyen
Phuong-Vi Nguyen
MSMaxwell Su
Maxwell Su
FCFátima María Cardozo
Fátima María Cardozo
AVAdriana Valenzuela
Adriana Valenzuela
Jesse J. WaggonerJesse J. Waggoner
Jesse J. Waggoner
SARS-CoV-2 variant detection relies on resource-intensive whole-genome sequencing methods. We sought to develop a scalable protocol for variant detection and surveillance in Paraguay, pairing rRT-PCR for spike mutations with Nanopore sequencing. A total of 201 acute-phase nasopharyngeal samples were included. Samples were positive for the SARS-CoV-2 N2 target and tested with the Spike SNP assay to detect mutations associated with the following variants: alpha (501Y), beta/gamma (417variant/484K/501Y), delta (452R/478K), and lambda (452Q/490S). Spike SNP calls were confirmed using amplicon (Sanger) sequencing and whole-genome (Nanopore) sequencing on a subset of samples with confirmed variant lineages. Samples had a mean N2 Ct of 20.8 (SD 5.6); 198/201 samples (98.5%) tested positive in the Spike SNP assay. The most common genotype was 417variant/484K/501Y, detected in 102/198 samples (51.5%), which was consistent with the P.1 lineage (gamma variant) in Paraguay. No mutations (K417 only) were found in 64/198 (32.3%), and K417/484K was identified in 22/198 (11.1%), consistent with P.2 (zeta). Seven samples (3.5%) tested positive for 452R without 478K, and one sample with genotype K417/501Y was confirmed as B.1.1.7 (alpha). The results were confirmed using Sanger sequencing in 181/181 samples, and variant calls were consistent with Nanopore sequencing in 29/29 samples. The Spike SNP assay could improve population-level surveillance for mutations associated with SARS-CoV-2 variants and inform the judicious use of sequencing resources.

10 January 2025 in Clinical Infectious Diseases
Verified
Journal Article
Closed access
JEJuan Espinosa-Pereiro
Juan Espinosa-Pereiro
AAAna Aguiar
Ana Aguiar
ENEva Megumi Nara
Eva Megumi Nara
AMAngelica Medina
Angelica Medina
GMGladys Molinas
Gladys Molinas
RDRaquel Duarte
Raquel Duarte
Background: Higher than standard doses of rifampicin could improve the treatment outcome of drug-susceptible tuberculosis (TB) without compromising the safety of patients. Methods: We performed a systematic review of prospective clinical studies including adults with pulmonary and extrapulmonary TB receiving rifampicin doses above 10 mg/kg/day. We extracted the data on overall adverse events (AE), hepatic AE, sputum culture conversion (SCC) at week 8, recurrence, mortality, and pharmacokinetics. We performed a Bayesian network meta-analysis (NMA) using a random-effects model. Results: In 19 studies, 2033 out of 3654 participants received rifampicin doses higher than 10 mg/kg/day. The NMA showed an increased risk of overall and hepatic AE for the 40 mg/kg/day dose (risk ratio [RR] 4.8, 95% credibility interval [CrI]: 1.1, 25, and 15.00; 95% CrI: 1.1, 58.0, respectively), but no other doses, including 50 mg/kg/day showed such an increase. Increasing doses improved sputum culture conversion at week 8 (RR 1.3, 95% CrI: 1.1, 1.7 for SCC with 35 mg/kg/day). Conclusions: Optimal doses of rifampicin may be between 25 and 35 mg/kg/day, but should be tailored at the individual or, at least, at the population level.

10 May 2023 in Viruses
Verified
Journal Article
Open access
PDF file
FPFlorencia del Puerto
Florencia del Puerto
Leticia Elizabeth Rojas VeraLeticia Elizabeth Rojas Vera
Leticia Elizabeth Rojas Vera
CAChyntia Carolina Díaz Acosta
Chyntia Carolina Díaz Acosta
LFLaura X. Franco
Laura X. Franco
FCFátima María Cardozo
Fátima María Cardozo
MCMiguela Ayala CANIZA
Miguela Ayala CANIZA
Soon after the declaration of the COVID-19 pandemic, the Institute for Health Sciences Research (IICS) of the National University of Asunción, Paraguay became a testing laboratory (COVID-Lab) for SARS-CoV-2. The COVID-Lab testing performance was assessed from 1 April 2020 to 12 May 2021. The effect of the pandemic on the IICS and how the COVID-Lab contributed to the academic and research activities of the institute were also assessed. IICS researchers and staff adjusted their work schedules to support the COVID-Lab. Of the 13,082 nasopharyngeal/oropharyngeal swabs processed, 2704 (20.7%) tested positive for SARS-CoV-2 by RT-PCR. Of the individuals testing positive, 55.4% were female and 48.3% were aged 21–40 years. Challenges faced by the COVID-Lab were unstable reagent access and insufficient staff; shifting obligations regarding research, academic instruction, and grantsmanship; and the continuous demands from the public for information on COVID-19. The IICS provided essential testing and reported on the progress of the pandemic. IICS researchers gained better laboratory equipment and expertise in molecular SARS-CoV-2 testing but struggled to manage their conflicting educational and additional research obligations during the pandemic, which affected their productivity. Therefore, policies protecting the time and resources of the faculty and staff engaged in pandemic-related work or research are necessary components of healthcare emergency preparedness.

26 April 2020 in Memorias del Instituto de Investigaciones en Ciencias de la Salud
Verified
Journal Article
Open access
PDF file
RRRocío Riveros-Maidana
Rocío Riveros-Maidana
AMAlejandro Méndez-Ferreira
Alejandro Méndez-Ferreira
NBNidia Benítez-Candia
Nidia Benítez-Candia
ENEva Megumi Nara
Eva Megumi Nara
DFDanilo Fernández-Ríos
Danilo Fernández-Ríos
La función original de los sistemas CRISPR/Cas es destruir el DNA de virus bacterianos. Este sistema ha evolucionado para identificar y cortar secuencias de diferentes DNA de virus de DNA evitando la infección. En la célula, está compuesto de genes Cas que producen nucleasas guiadas por RNA capaces de cortar el DNA. Si el RNA guía encuentra DNA de un virus con el que se puede emparejar, recluta a la nucleasa Cas9 que lo corta. Este sistema es utilizado in vitro para editar genes basándose en la producción de rupturas de doble cadena y su posterior reparación. Actualmente existen varias plataformas para el diseño de RNAs guía, aunque también es posible realizarlo de forma manual. Los componentes del sistema son entregados a la célula mediante un plásmido o una ribonucleoproteína. En esta revisión nos centraremos en la función original de CRISPR/Cas en procariotas y en cómo los investigadores la han modificado para proporcionar nuevas técnicas de edición de genomas. Discutiremos sobre las ventajas de esta nueva técnica, las formas en que podemos utilizarla y algunas de las limitaciones que aún encontramos en su aplicación.

24 September 2025 in Viruses
Verified
Journal Article
Open access
PDF file
MVMARIA FATIMA RODRIGUEZ VALINOTI
MARIA FATIMA RODRIGUEZ VALINOTI
ENEva Megumi Nara
Eva Megumi Nara
MMMagaly Martinez
Magaly Martinez
RVRosmary Rodriguez Valinotti
Rosmary Rodriguez Valinotti
ASAntonio Rodriguez Sanchez
Antonio Rodriguez Sanchez
Bovine viral diarrhea virus (BVDV) is the most prevalent pathogen in cattle and causes significant economic losses due to its severe clinical manifestations. It belongs to the family Flaviviridae and is distributed in species A, B, and H within the genus Pestivirus. The objective of this study was to detect and characterize BVDV using molecular techniques (RT-PCR) in semen and aborted fetuses samples that were sent to the CEDIVEP (Veterinary Diagnostic Center of Paraguay) laboratory. Seventy-three samples of semen from bulls were analyzed, and 54.7% of the samples were positive for Pestivirus A. The presence of Pestivirus A and H was detected in 2/8 spontaneously aborted fetuses. The genotypes of four individual samples of type A and four samples of type H organs were confirmed by partial sequencing of the 5-UTR region. The presence of BVDV was confirmed by molecular techniques for the first time in our country through its detection in different types of samples, as well as the presence of two genotypes. This suggests that the circulation of this virus can cause significant losses in cattle production in Paraguay.