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G-quadruplexes (G4s) are non-canonical structures of DNA or RNA formed in guanine-rich regions and play crucial roles in several processes related to the central dogma of molecular biology. G4s have been identified in some medically important viruses, such as SARS-COV-2 or HIV, making them potential molecular targets for diagnostics and antiviral development. However, not much is known about DNA viruses, as the Human Papillomavirus (HPV), the etiological agent of several types of cancers worldwide. The present study aims to identify G4 structures in the genomes of High-Risk (HR) HPV types 16, 18, and 58 using in silico methods. Initially, we selected bioinformatics predictors based on established criteria and identified Putative Quadruplex Sequences (PQS) in the genomes of these three HR-HPVs, as well as in their circulating variants. Finally, we modeled a conserved atypical G4 structure in 3D. Our results indicated more than 100 SFG4 in each genotype, with a higher abundance in L2, E1 and L1 genes. Furthermore, we identified two conserved PQS in the L1 region, which encodes the main structural protein, across all three HPVs, showing > 80 % identity. These same motifs were also found in clinical samples (n = 992) and could therefore serve as potential molecular targets. [ABSTRACT FROM AUTHOR]

The most widely used class of antivirals available for Influenza treatment are the neuraminidase inhibitors (NAI) Oseltamivir and Zanamivir. However, amino acid (AA) substitutions in the neuraminidase may cause reduced inhibition or high antiviral resistance. In Mexico, the current state of knowledge about NAI susceptibility is scarce, in this study we report the results of 14 years of Influenza surveillance by phenotypic and genotypic methods. A total of 255 isolates were assessed with the NAI assay, including Influenza A(H1N1)pdm09, A(H3N2) and Influenza B (IBV). Furthermore, 827 sequences contained in the GISAID platform were analyzed in search of relevant mutations.Overall, five isolates showed highly reduced inhibition or reduced inhibition to Oseltamivir, and two showed reduced inhibition to Zanamivir in the NAI assays. Additionally, five A(H1N1)pdm09 sequences from the GISAID possessed AA substitutions associated to reduced inhibition to Oseltamivir and none to Zanamivir. Oseltamivir resistant A(H1N1)pdm09 harbored the H275Y mutation. No genetic mutations were identified in Influenza A(H3N2) and IBV. Overall, these results show that in Mexico the rate of NAI resistance is low (0.6%), but it is essential to continue the Influenza surveillance in order to understand the drug susceptibility of circulating strains., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

High-Risk Human Papillomavirus (HR-HPV) types 16 and 18 are estimated to be responsible for 72.4% of all HPV-related cancers worldwide in both men and women, including cervical, anal, penile, vulval, vaginal and head and neck cancers [1]. Important efforts worldwide have devoted to the study of these genotypes, throughout epidemiology and basic science approaches. Of particular interest are the genes from the early region (E), coding non-structural proteins. Early genes E1 and E2 products are involved in replication and transcription regulation, while E6 and E7 proteins are recognised for their oncogenic potential. In this data report, we described a set of primers based on reference sequences from HPV16 and HPV18 designed to cover the early region of these oncogenic genotypes. The design was based on multiple sequences alignment to identify the less conserved regions along the open reading frames (ORFs) E6, E7, E1 and E2. The design allows a highly stringent real time PCR essay ranged from 123 to 598 bp overlapping products for HPV16 (12 products in total) and from 183 to 526 bp for HPV18 (11 products in total), both spanning the early genomic region. The high annealing temperatures (Ta) and regions selected for primer bind were intended for genotypic specificity, without compromising the qPCR amplification efficiency (≥ 90%). Evaluation of qPCR conditions for primer set was performed using DNA standards as controls, generated from the HPV16 and 18 genomes clones. This provides relevant information for further multiple quantitative real-time PCR analysis (qPCR), using the SYBR green chemistry, which is is more affordable than generating multiple fluorescently labeled probes., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2023 The Authors.)

Several vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been approved for controlling the coronavirus disease 2019 (COVID-19) pandemic worldwide. Antibody response is essential to understand the immune response to different viral targets after vaccination with different vaccine platforms. Thus, the main aim of this study was to describe how vaccination with two distinct SARS-CoV-2 vaccine preparations elicit IgG antibody specific responses against two antigenically relevant SARS-CoV-2 viral proteins: the receptor-binding domain (RBD) and the full-length spike (S). To do so, SARS-CoV-2 protein specific in-house enzyme-linked immunosorbent assays (ELISAs) were standardized and tested against serum samples collected from 89 adults, recipients of either a single-dose of the Spike-encoding mRNA-based Pfizer/BioNTech (Pf-BNT) (70%, 62/89) or the Spike-encoding-Adenovirus-5-based CanSino Biologics Inc. (CSBIO) (30%, 27/89) in Merida, Mexico. Overall, we identified an IgG seroconversion rate of 88% (68/78) in all vaccinees after more than 25 days post-vaccination (dpv). Anti-RBD IgG-specific responses ranged from 90% (46/51) in the Pf-BNT vaccine at 25 dpv to 74% (20/27) in the CSBIO vaccine at 42 dpv. Compared to the S, the RBD IgG reactivity was significantly higher in both Pf-BNT ( p < 0.004) and CSBIO ( p < 0.003) vaccinees. Interestingly, in more than 50% of vaccine recipients, with no history of COVID-19 infection, antibodies against the nucleocapsid (N) protein were detected. Thus, participants were grouped either as naïve or pre-exposed vaccinees. Seroconversion rates after 25 and more dpv varies between 100% in Pf-BNT (22/22) and 75% (9/12) in CSBIO pre-exposed vaccinees, and 89% (26/29) and 73% (11/15) in Pf-BNT and CSBIO naïve vaccine recipients, respectively. In summary, observed seroconversion rates varied depending on the type of vaccine, previous infection with SARS-CoV-2, and the target viral antigen. Our results indicate that both vaccine preparations can induce detectable levels of IgG against the RBD or Spike in both naïve and SARS-CoV-2 pre-exposed vaccinees. Our study provides valuable and novel information about the serodiagnosis and the antibody response to vaccines in Mexico., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Puerta-Guardo, Parra-Cardeña, Peña-Miranda, Flores-Quintal, Granja-Pérez, Villanueva-Jorge, González-Losa, Conde-Ferraez, Gómez-Carballo, Vazquez-Prokopec, Earnest, Manrique-Saide and Ayora-Talavera.)

Objective: To analyze the presenceof human papillomavirus in prostate and its associationwith prostate cancer. METHODS: A case-control study was conducted.Tissue samples with benign hyperplasia and prostatecancer were collected. Risk factors related to prostatecancer and human papillomavirus were assessedby a medical interview. Prostate tissue was obtainedby transrectal biopsy or transurethral resection. Theidentification of viral genome was assessed by the amplificationof 450 pb., from L1 gene. Real time PCR wasused to identified HPV genotypes 16 and 18. For dataanalysis, the χ2 test, Student's T test or Mann-WhitneyU test and OR were computed. RESULTS: Thirty and 99 with benign prostatehyperplasia were included in a 1:3 ratio, with a meanage of 69.44±9.22 years. The global prevalence of humanpapillomavirus was 15.2% being similar in bothcases (15.6%) and controls (15.1%) with no significantdifference (p = 0.572). Forty percent of the infectionswere persistent. From all positive samples, only in the40% were identified some of the genotypes analyzed(16 and 18). The group of patients with Gleason scorede > 7 had a virus prevalence of 16%., Conclusions: The results show the presence ofthe human papillomavirus genome in prostate tissuewith and without neoplasia; no association was foundbetween infection and prostate cancer.

Aloe vera is a crop of wide economic value of worldwide distribution, and a rich source of quinone components. Recently, antiviral aloe anthraquinones had been reported against human influenza virus. In the present work two anthraquinones, aloesaponarin-I ( 1 ) and aloesaponarin-II ( 2 ) were isolated from A. vera roots, and six derivatives were obtained by methylation ( 3 ), acetylation ( 4 ) and O -glycosyl ( 5-6 ) reactions starting from ( 1 ). Additionally, a new Tetra- O -acetyl-β-d-glucopyranosyl derivative from 2 was also prepared. All compounds were evaluated against two strains of influenza virus AH1N1 by cytopathic effect reduction assay (CPE). The antiviral activity was determined by the ability of compounds to inhibit virus replication on Madin Darby Canine Kidney cells (MDCK). New derivatives 3-(2´,3´,4´,6´-Tetra-O-acetyl-β-d-glucopyranosyl-aloesaponarin-I ( 5 ) and 3 -(2´,3´,4´,6´-Tetra-O-acetyl-β-d-glucopyranosyl- aloesaponarin-II ( 7 ) showed a cytopathic reduction effect against influenza strain A/Yucatán/2370/09 with IC 50 of 30.77 and 13.70 μM, and against the virus A/Mexico/InDRE797/10 with IC 50 of 62.28 and 19.47 μM, respectively. To assess the effect of derivatives 5 and 7 during one cycle of replication (0-10 h), a time-of-addition experiment was performed. As a result it was found that both compounds were most effective when added 6-10 h post-infection and significantly inhibited viral titre (> 70%) at the concentrations of 50 and 100 μM. Based on the structural analysis of the compounds, it was suggested that the Tetra-O-acetyl-β-d-glucopyranosyl substituent at the C3 position of the anthraquinone might have an effect against the influenza AH1N1 virus., (© 2019 Elsevier B.V. All rights reserved.)

The 2012 and 2013 annual influenza epidemics in Mexico were characterized by presenting different seasonal patterns. In 2012 the A(H1N1)pdm09 virus caused a high incidence of influenza infections after a two-year period of low circulation; whereas the 2013 epidemic presented circulation of the A(H1N1)pdm09 virus throughout the year. We have characterized the molecular composition of the Hemagglutinin (HA) and Neuraminidase (NA) genes of the A(H1N1)pdm09 virus from both epidemic seasons, emphasizing the genetic characteristics of viruses isolated from Yucatan in Southern Mexico. The molecular analysis of viruses from the 2012 revealed that all viruses from Mexico were predominantly grouped in clade 7. Strikingly, the molecular characterization of viruses from 2013 revealed that viruses circulating in Yucatan were genetically different to viruses from other regions of Mexico. In fact, we identified the occurrence of two genetic variants containing relevant mutations at both the HA and NA surface antigens. There was a difference on the temporal circulation of each genetic variant, viruses containing the mutations HA-A141T / NA-N341S were detected in May, June and July; whereas viruses containing the mutations HA-S162I / NA-L206S circulated in August and September. We discuss the significance of these novel genetic changes.

Introduction: While vaccination may be relatively straightforward for regions with a well-defined winter season, the situation is quite different for tropical regions. Influenza activity in tropical regions might be out of phase with the dynamics predicted for their hemispheric group thereby impacting the effectiveness of the immunization campaign., Objective: To investigate how the climatic diversity of Mexico hinders its existing influenza immunization strategy and to suggest that the hemispheric vaccine recommendations be tailored to the regional level in order to optimize vaccine effectiveness., Methods: We studied the seasonality of influenza throughoutMexico by modeling virological and mortality data.De-trended time series of each Mexican state were analyzed by Fourier decomposition to describe the amplitude and timing of annual influenza epidemic cycles and to compare with each the timing of the WHO's Northern and Southern Hemispheric vaccination schedule., Findings: The timings of the primary (major) peaks of both virological and mortality data for most Mexican states are well aligned with the Northern Hemisphere winter (December-February) and vaccine schedule. However, influenza peaks in September in the three states of the Yucatan Peninsula. Influenza-related mortality also peaks in September in Quintana Roo and Yucatan whereas it peaks in May in Campeche. As the current timing of vaccination in Mexico is between October and November, more than half of the annual influenza cases have already occurred in the Yucatan Peninsula states by the time the Northern Hemispheric vaccine is delivered and administered., Conclusion: The current Northern Hemispheric influenza calendar adopted for Mexico is not optimal for the Yucatan Peninsula states thereby likely reducing the effectiveness of the immunization of the population. We recommend that Mexico tailor its immunization strategy to better reflect its climatologic and epidemiological diversity and adopt the WHO Southern Hemisphere influenza vaccine and schedule for the Yucatan Peninsula., (Copyright © 2017 Elsevier Ltd. All rights reserved.)