Genomic Analysis of Early SARS-CoV-2 Variants Introduced in Mexico.

The coronavirus disease 2019 (COVID-19) pandemic has affected most countries in the world. Studying the evolution and transmission patterns in different countries is crucial to enabling implementation of effective strategies for disease control and prevention. In this work, we present the full genome sequence for 17 SARS-CoV-2 isolates corresponding to the earliest sampled cases in Mexico. Global and local phylogenomics, coupled with mutational analysis, consistently revealed that these viral sequences are distributed within 2 known lineages, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineage A/G, containing mostly sequences from North America, and lineage B/S, containing mainly sequences from Europe. Based on the exposure history of the cases and on the phylogenomic analysis, we characterized 14 independent introduction events. Additionally, three cases with no travel history were identified. We found evidence that two of these cases represented local transmission cases occurring in Mexico during mid-March 2020, denoting the earliest events described for the country. Within this local transmission cluster, we also identified an H49Y amino acid change in the Spike protein. This mutation represents a homoplasy occurring independently through time and space and may function as a molecular marker to follow any further spread of these viral variants throughout the country. Our results provide a general picture of the SARS-CoV-2 variants introduced at the beginning of the outbreak in Mexico, setting the foundation for future surveillance efforts.IMPORTANCE Understanding the introduction, spread, and establishment of SARS-CoV-2 within distinct human populations as well as the evolution of the pandemics is crucial to implement effective control strategies. In this work, we report that the initial virus strains introduced in Mexico came from Europe and the United States and that the virus was circulating locally in the country as early as mid-March. We also found evidence for early local transmission of strains with a H49Y mutation in the Spike protein, which could be further used as a molecular marker to follow viral spread within the country and the region.

[Mixed analysis of the satisfaction survey of the Primary Health Care course of the Institute of Health for Well-being]. / Análisis mixto de la encuesta de satisfacción del curso de Atención Primaria de Salud del Instituto de Salud para el Bienestar.

Background: Describing the perception towards the online course on Primary Health Care (PHC) of the Institute of Health for Well-being (INSABI) will allow to establish improvement actions. Objective: Describe the factors that contribute to satisfaction with the PHC course offered online by INSABI. Material and methods: 620 records of the Health Education System for Well-being were studied. Satisfaction was determined using a Likert-type questionnaire with three dimensions: virtual environment, cognitive area, and measurement of learning. A deductive analysis of the open opinions was carried out. Results: 70% of the health personnel approved the course in less than a week, with an initial score of 5.41 ±1.9 points and final score of 7.8 ± 1.2. More than 65% had scores above the average in the three dimensions. Satisfaction with the virtual environment was 15.57 ± 3.4 points, and 15.73 ± 3.3 with the cognitive dimension. Age and gender were associated with dissatisfaction with the virtual environment and in the cognitive dimension, age was associated with dissatisfaction; 27.7% expressed negative comments, 28.5% related to course extension; 15.5% about the didactic techniques, 10.9% about the speakers and 10.4% about the final exam. Conclusions: The course generates significant learning, 62.4% of the students have a positive or neutral opinion. However, 27.8% expressed dissatisfaction, the majority related to the extension of the course.

Introducción: describir la percepción hacia el curso en línea de Atención Primaria de Salud (APS) del Instituto de Salud para el Bienestar (INSABI) permitirá establecer acciones de mejora. Objetivo: conocer el grado de satisfacción con el curso sobre APS que el INSABI ofrece en línea mediante un análisis mixto. Material y métodos: se estudiaron 620 registros del Sistema Educativo de Salud para el Bienestar. La satisfacción se determinó mediante un cuestionario tipo Likert con tres dimensiones: ambiente virtual, área cognitiva y medición del aprendizaje. Se realizó un análisis deductivo de las opiniones abiertas. Resultados: el 70% de los trabajadores de la salud aprobaron el curso en menos de una semana con una calificación inicial de 5.41 ± 1.9 puntos y la final de 7.8 ± 1.2. Más del 65% tuvieron puntuaciones por arriba de la media en las tres dimensiones. La satisfacción con el ambiente virtual fue de 15.57 ± 3.4 puntos, y de 15.73 ± 3.3 con la dimensión cognitiva. La edad y el sexo se asociaron a insatisfacción con el ambiente virtual y en la dimensión cognitiva, la edad se asoció con insatisfacción; el análisis cualitativo mostró que 27.7% expresaron comentarios negativos, 28.5% relacionadas con la extensión del curso; 15.5% sobre las técnicas didácticas, 10.9% acerca de los ponentes y 10.4% sobre el examen final. Conclusiones: el curso genera aprendizaje significativo, el 62.4% de los educandos tienen una opinión positiva o neutra. Sin embargo, 27.8% manifestaron insatisfacción, la mayoría relacionada con la extensión del curso.

[Development of the INSABI educational strategy: a lesson learned from the COVID-19 epidemic]. / Desarrollo de la estrategia educativa del INSABI: una lección aprendida a partir de la epidemia de COVID-19.

The Institute for Health for Well-being (INSABI according to its initials in Spanish), in collaboration with the National Institute of Medical Sciences and Nutrition Salvador Zubirán (INCMNSZ), instituted the Continuous Training on clinical management "Mexico against COVID-19" in 2020, with the purpose of training the frontline health personnel in the care for patients with COVID-19 in the context of hospital reconversion through the COVIDUTI platform. Virtual conferences were held for medical personnel from all over the country with the possibility of interacting with various specialists. In 2020, 215 sessions were held and 158 in 2021. That year educational content was expanded and included topics for other health categories, such as nursing and social work. In October 2021, it was established the Health Educational System for Well-being (SIESABI), with the aim of promoting continuous and permanent education for health workers. It currently offers face-to-face and virtual courses, permanent seminars, and telementoring, with the possibility of providing academic follow-up to its subscribers and linking priority courses that are on other platforms. The educational platform is an opportunity to unify the efforts of the health system in Mexico in the continuous and permanent education of professionals who care for people without social security and thereby contribute to the implementation of a model of care based on primary health care (PHC).

El Instituto de Salud para el Bienestar (INSABI), en colaboración con el Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ), instituyó el entrenamiento continuo sobre manejo clínico "México contra COVID-19" en 2020, con el propósito de capacitar al personal de salud de primera línea en la atención de pacientes con COVID-19 en el contexto de la reconversión hospitalaria mediante la plataforma COVIDUTI. Se realizaron conferencias virtuales dirigidas a personal médico de todo el país con la posibilidad de interactuar con diversos especialistas. En 2020 se realizaron 215 sesiones y 158 en 2021. Ese año se ampliaron contenidos educativos y se incluyeron temas para otras categorías de salud, como enfermería y trabajo social. En octubre de 2021 se estableció el Sistema Educativo de Salud para el Bienestar (SIESABI), con el objetivo de promover la educación continua y permanente para los trabajadores de la salud. Actualmente ofrece cursos presenciales, virtuales, seminarios permanentes y telementorías, con la posibilidad de dar seguimiento académico a sus suscriptores y vincular cursos prioritarios que están en otras plataformas. La plataforma educativa es una oportunidad para unificar los esfuerzos del sistema de salud en México en la educación continua y permanente de los profesionales que atienden a personas sin seguridad social y, con ello, contribuir en la implementación de un modelo de atención basado en Atención Primaria de Salud (APS).

A Multimodal Strategy to Reduce the Risk of Hospitalization/death in Ambulatory Patients with COVID-19.

BACKGROUND: Different interventions have been implemented worldwide for the house-hold monitoring of patients with mild COVID-19 to reduce the burden of healthcare systems and guarantee quality of care. Telephone follow up and treatment kits have not been evaluated in the context of a national-wide primary care program. AIM OF THE STUDY: To compare the risk of hospitalization and death for COVID-19 between ambulatory patients who received and those who did not receive a treatment kit and telephone follow-up in a developing country METHODS: A two-group comparative analysis was conducted using data from the medical information systems of the Mexican Institute of Social Security. We included a total of 28,048 laboratory-confirmed SARS-CoV-2 patients: 7,898 (28.2%) received a medical kit and 20,150 (71.8%) did not. The incidence rates of hospitalization and death combined were calculated. To identify significant associations between hospitalization or death and treatment medical kits, we calculated the risk ratios using a multivariate logistic model. RESULTS: The incidence of hospitalization was 6.14% in patients who received a kit and 11.71% in those who did not. Male sex, age, and a medical history of obesity, hypertension, diabetes, immunosuppression, or kidney disease were associated with increased risk of hospitalization or death. The risk rates were reduced in patients who received a medical kit or telephone follow-up. In the multivariate model, receiving a medical kit was associated with a lower risk of hospitalization or death from COVID-19: adjusted risk ratio 0.41 (95% confidence interval 0.36-0.47). CONCLUSION: Use of a multimodal strategy may reduce the risk of hospitalization and death in adult outpatients with mild COVID-19.

Low Prevalence of ETV6::RUNX1 Fusion Gene in a Hispanic Population.

ETV6::RUNX1 is a genetic rearrangement of good prognosis in children with acute lymphoblastic leukemia (ALL). In Mexico, its prevalence is low in comparison with Caucasian populations. We developed a novel TaqMan one-step RT-qPCR approach to assess the prevalence of four genetic rearrangements in a cohort of Hispanic children with ALL from Mexico City. The prevalence of common fusion gene transcripts was as follows: TCF3::PBX1 7.7%; BCR::ABL1p 190 3.3%; and KMT2A::AFF1 2.8%, and ETV6::RUNX1was observed with low prevalence (10.5%) in comparison to that reported for developed countries. This is consistent with previous findings on Mexican children with ALL and similar to those reported on children from Hispanic populations. The confirmation of a low prevalence of ETV6::RUNX1 in children of a Hispanic origin represents an advancement in the description of genetic factors of ALL in these populations.

Structural Characterization of Haemophilus influenzae Enolase and Its Interaction with Human Plasminogen by In Silico and In Vitro Assays.

Haemophilus influenzae is the causal agent of invasive pediatric diseases, such as meningitis, epiglottitis, pneumonia, septic arthritis, pericarditis, cellulitis, and bacteremia (serotype b). Non-typeable H. influenzae (NTHi) strains are associated with localized infections, such as otitis media, conjunctivitis, sinusitis, bronchitis, and pneumonia, and can cause invasive diseases, such as as meningitis and sepsis in immunocompromised hosts. Enolase is a multifunctional protein and can act as a receptor for plasminogen, promoting its activation to plasmin, which leads to the degradation of components of the extracellular matrix, favoring host tissue invasion. In this study, using molecular docking, three important residues involved in plasminogen interaction through the plasminogen-binding motif (251EFYNKENGMYE262) were identified in non-typeable H. influenzae enolase (NTHiENO). Interaction with the human plasminogen kringle domains is conformationally stable due to the formation of four hydrogen bonds corresponding to enoTYR253-plgGLU1 (K2), enoTYR253-plgGLY310 (K3), and enoLYS255-plgARG471/enoGLU251-plgLYS468 (K5). On the other hand, in vitro assays, such as ELISA and far-western blot, showed that NTHiENO is a plasminogen-binding protein. The inhibition of this interaction using polyclonal anti-NTHiENO antibodies was significant. With these results, we can propose that NTHiENO-plasminogen interaction could be one of the mechanisms used by H. influenzae to adhere to and invade host cells.

SARS-CoV-2 IgG Antibodies Seroprevalence and Sera Neutralizing Activity in MEXICO: A National Cross-Sectional Study during 2020.

Until recently, the incidence of COVID-19 was primarily estimated using molecular diagnostic methods. However, the number of cases is vastly underreported using these methods. Seroprevalence studies estimate cumulative infection incidences and allow monitoring of transmission dynamics, and the presence of neutralizing antibodies in the population. In February 2020, the Mexican Social Security Institute began conducting anonymous unrelated sampling of residual sera from specimens across the country, excluding patients with fever within the previous two weeks and/or patients with an acute respiratory infection. Sampling was carried out weekly and began 17 days before Mexico's first officially confirmed case. The 24,273 sera obtained were analyzed by chemiluminescent-linked immunosorbent assay (CLIA) IgG S1/S2 and, later, positive cases using this technique were also analyzed to determine the rate of neutralization using the enzyme-linked immunosorbent assay (ELISA). We identified 40 CLIA IgG positive cases before the first official report of SARS-CoV-2 infection in Mexico. The national seroprevalence was 3.5% in February and 33.5% in December. Neutralizing activity among IgG positives patients during overall study period was 86.1%. The extent of the SARS-CoV-2 infection in Mexico is 21 times higher than that reported by molecular techniques. Although the general population is still far from achieving herd immunity, epidemiological indicators should be re-estimated based on serological studies of this type.

Increased expression of hypoxia-induced factor 1α mRNA and its related genes in myeloid blood cells from critically ill COVID-19 patients.

BACKGROUND: COVID-19 counts 46 million people infected and killed more than 1.2 million. Hypoxaemia is one of the main clinical manifestations, especially in severe cases. HIF1α is a master transcription factor involved in the cellular response to oxygen levels. The immunopathogenesis of this severe form of COVID-19 is poorly understood. METHODS: We performed scRNAseq from leukocytes from five critically ill COVID-19 patients and characterized the expression of hypoxia-inducible factor1α and its transcriptionally regulated genes. Also performed metanalysis from the publicly available RNAseq data from COVID-19 bronchoalveolar cells. RESULTS: Critically-ill COVID-19 patients show a shift towards an immature myeloid profile in peripheral blood cells, including band neutrophils, immature monocytes, metamyelocytes, monocyte-macrophages, monocytoid precursors, and promyelocytes-myelocytes, together with mature monocytes and segmented neutrophils. May be the result of a physiological response known as emergency myelopoiesis. These cellular subsets and bronchoalveolar cells express HIF1α and their transcriptional targets related to inflammation (CXCL8, CXCR1, CXCR2, and CXCR4); virus sensing, (TLR2 and TLR4); and metabolism (SLC2A3, PFKFB3, PGK1, GAPDH and SOD2). CONCLUSIONS: The up-regulation and participation of HIF1α in events such as inflammation, immunometabolism, and TLR make it a potential molecular marker for COVID-19 severity and, interestingly, could represent a potential target for molecular therapy. Key messages Critically ill COVID-19 patients show emergency myelopoiesis. HIF1α and its transcriptionally regulated genes are expressed in immature myeloid cells which could serve as molecular targets. HIF1α and its transcriptionally regulated genes is also expressed in lung cells from critically ill COVID-19 patients which may partially explain the hypoxia related events.

A Shift Towards an Immature Myeloid Profile in Peripheral Blood of Critically Ill COVID-19 Patients.

BACKGROUND: SARS-CoV-2, the etiological agent causing COVID-19, has infected more than 27 million people with over 894000 deaths worldwide since its emergence in December 2019. Factors for severe diseases, such as diabetes, hypertension, and obesity have been identified however, the precise pathogenesis is poorly understood. To understand its pathophysiology and to develop effective therapeutic strategies, it is essential to define the prevailing immune cellular subsets. METHODS: We performed whole circulating immune cells scRNAseq from five critically ill COVID-19 patients, trajectory and gene ontology analysis. RESULTS: Immature myeloid populations, such as promyelocytes-myelocytes, metamyelocytes, band neutrophils, monocytoid precursors, and activated monocytes predominated. The trajectory with pseudotime analysis supported the finding of immature cell states. While the gene ontology showed myeloid cell activation in immune response, DNA and RNA processing, defense response to the virus, and response to type 1 interferon. Lymphoid lineage was scarce. Expression of genes such as C/EBPß, IRF1and FOSL2 potentially suggests the induction of trained immunity. CONCLUSIONS: Our results uncover transcriptomic profiles related to immature myeloid lineages and suggest the potential induction of trained immunity.

Molecular Detection and Typing of Human Papillomavirus in Men from Northwestern Mexico.

BACKGROUND: A few studies of Human Papillomavirus (HPV) distribution and frequency have shown a real context of infection in men. The study aimed to know the HPV types distribution in men from Northwestern Mexico, in general, per age and year. METHODS: A total of 1,769 males were recruited from 5 years (2011-2015), from an HPV PCR testing laboratory service. Penile scraps from urethral meatus and coronal sulcus were taken for DNA isolation. There were detected 32 high and low-risk HPV types by HPV Type 3.5 LCD-Array system. RESULTS: A high frequency of HPV-6 and HPV-66 and a reduced frequency of HPV-18 and HPV-11 was detected. Young men had a high risk of HPV infection regarding men aged 40 years and older. The theoretical coverage for the HPV vaccine in men was calculated, where the bivalent vaccine showed coverage of 21.66% in high-risk HPV positive cases. CONCLUSION: The men from Northwestern Mexico have a different distribution of high and low-risk HPV types and high risk of HPV infection in younger men, with a theoretical coverage for HPV bivalent vaccine of 1 of 10 positive men for any HPV type.

Molecular Alterations Prompted by SARS-CoV-2 Infection: Induction of Hyaluronan, Glycosaminoglycan and Mucopolysaccharide Metabolism.

BACKGROUND: The SARS-CoV-2 is the etiological agent causing COVID-19 which has infected more than 2 million people with more than 200000 deaths since its emergence in December 2019. In the majority of cases patients are either asymptomatic or show mild to moderate symptoms and signs of a common cold. A subset of patients, however, develop a severe atypical pneumonia, with the characteristic ground-glass appearance on chest x-ray and computerized tomography, which evolves into an acute respiratory distress syndrome, that requires mechanical ventilation and eventually results in multiple organ failure and death. The Molecular pathogenesis of COVID-19 is still unknown. AIM OF THE STUDY: In the present work we performed a stringent metanalysis from the publicly available RNAseq data from bronchoalveolar cells and peripheral blood mononuclear cells to elucidate molecular alterations and cellular deconvolution to identify immune cell profiles. RESULTS: Alterations in genes involved in hyaluronan, glycosaminoglycan and mucopolysaccharides metabolism were over-represented in bronchoalveolar cells infected by SARS-CoV-2, as well as potential lung infiltration with neutrophils, T CD4+ cell and macrophages. The blood mononuclear cells presented a proliferative state. Dramatic reduction of NK and T lymphocytes, whereas an exacerbated increase in monocytes. CONCLUSIONS: In summary our results revealed molecular pathogenesis of the SARS-CoV-2 infection to bronchoalveolar cells inducing the hyaluronan and glycosaminoglycan metabolism that could shape partially the components of the ground-glass opacities observed in CT. And the potential immune response profile in COVID-19.

[Occupational exposure-associated hematological and immunologic manifestations to the benzene-toluene-xylene (Btx) mixture]. / Exposición ocupacional a mezcla de benceno-tolueno-xileno. Manifestaciones hematoinmunológicas.

Despite, the idea promoted to study occupational exposure to benzene and its mixture with toluene and xylene (BTX) because it appears to determine its toxicity and probably the production of additive effects, it persists interest to recognizing its hematological and immunotoxic effects. The fact that exposure to a sole substance in the occupational field is infrequent. Available contributions that analyze these implications are scarce, with contradictory results, and in their majority are limited to the fraction of benzene. Epidemiologic studies that have evaluated occupational exposure to any of the BTX fractions have been based on personal monitoring, while others have characterized this heterogeneously and are accompanied by weaker proposals. The conformation of specific methods to stimulate occupational exposure to the BTX mixture would contribute to its homogenization and allow for a more integral view in terms of determining BTX exposure. On the other hand, the application of BTX exposure biomarkers has been questioned in studies contemplating the specific biological effects of reference-associated chronic exposure. Analysis of the hematological and immunologic manifestations associated BTX mixture is based on information that is unclear, controversial, or even speculative to date.

Evolutionary analysis of the Chikungunya virus epidemic in Mexico reveals intra-host mutational hotspots in the E1 protein.

The epidemic potential of Chikungunya virus (CHIKV) was recently made evident by its introduction and rapid expansion in the Caribbean and the Americas. We sought to gain a detailed understanding of the dynamics of the epidemic in Mexico, the country with the highest number of confirmed CHIKV cases in the Americas, and to characterise viral evolution at the population and intra-host level. Analysis of the spatiotemporal distribution of 2,739 diagnosed cases in Mexico from December 2014 to December 2015 showed a rapid nationwide expansion of the epidemic with focalisation in the South West of the country. We sequenced the envelope glycoprotein 1 gene (E1) from 25 patients using the Illumina MiSeq platform and report synonymous and non-synonymous consensus mutations. Bayesian phylogenetic analysis using 249 Asian lineage E1 sequences gave updated estimates of nucleotide substitution rates for E1 and time to most recent common ancestor of major lineages. The analysis indicates phylogenetically-related emergent Latin American clusters in South Western Mexico, Nicaragua and Honduras and transmission of American strains in the Pacific islands. Detailed analysis showed that intra-host changes in E1 mainly occurred in two variable regions (E1:189-220 and E1:349-358) in domains II and III, respectively, in residues involved in inter and intra-envelope spike interactions. At the population level, this study sheds light on the introduction and evolutionary dynamics of CHIKV in the Americas. At the intra-host level, this study identifies mutational hotspots of the E1 protein with implications for understanding the relationship between the CHIKV quasispecies, viral fitness and pathogenesis.

Prevalence of non-influenza respiratory viruses in acute respiratory infection cases in Mexico.

BACKGROUND: Acute respiratory infections are the leading cause of morbidity and mortality worldwide. Although a viral aetiological agent is estimated to be involved in up to 80% of cases, the majority of these agents have never been specifically identified. Since 2009, diagnostic and surveillance efforts for influenza virus have been applied worldwide. However, insufficient epidemiological information is available for the many other respiratory viruses that can cause Acute respiratory infections. METHODS: This study evaluated the presence of 14 non-influenza respiratory viruses in 872 pharyngeal exudate samples using RT-qPCR. All samples met the operational definition of a probable case of an influenza-like illness or severe acute respiratory infection and had a previous negative result for influenza by RT-qPCR. RESULTS: The presence of at least one non-influenza virus was observed in 312 samples (35.8%). The most frequent viruses were rhinovirus (RV; 33.0%), human respiratory syncytial virus (HRSV; 30.8%) and human metapneumovirus (HMPV; 10.6%). A total of 56 cases of co-infection (17.9%) caused by 2, 3, or 4 viruses were identified. Approximately 62.5% of all positive cases were in children under 9 years of age. CONCLUSION: In this study, we identified 13 non-influenza respiratory viruses that could occur in any season of the year. This study provides evidence for the prevalence and seasonality of a wide range of respiratory viruses that circulate in Mexico and constitute a risk for the population. Additionally, our data suggest that including these tests more widely in the diagnostic algorithm for influenza may reduce the use of unnecessary antibiotics, reduce the hospitalisation time, and enrich national epidemiological data with respect to the infections caused by these viruses.

Early mortality in children with acute lymphoblastic leukemia in a developing country: the role of malnutrition at diagnosis. A multicenter cohort MIGICCL study.

The role of malnutrition at diagnosis as a predictor of early mortality in Mexican leukemia children remains controversial. The objective of present study was to investigate whether malnutrition was a predictor of early mortality during the first year of treatment in Mexican acute lymphoblastic leukemia (ALL) children through the first population-based study. A total of 794 newly diagnosed ALL pediatric patients from public hospitals of Mexico City were enrolled. A multivariate Cox proportional hazards regression model was constructed and adjusted by patient's age at diagnosis, gender, hospital of treatment, and socioeconomic status. Early mortality was high (12.1%) and malnutrition by different indicators was not associated with mortality at induction phase and at 6th month; a high risk of dying (RR = 2.08; 95% CI: 1.08-4.01) was observed in the group of malnourished children with a high-risk ALL.

Detection of Mycobacterium tuberculosis from respiratory samples with the liquid culture system MB/BacT and verified by PCR.

OBJECTIVE: To assess the performance in the clinical setting of the MB/BacT system for isolation of Mycobacterium tuberculosis and to verify by PCR. MATERIAL AND METHODS: The study included 272 sputum samples from 208 patients with the presumptive diagnosis of pulmonary tuberculosis. ZN was made, culture in Löwenstein-Jensen medium, MB/BacT and PCR. RESULTS: Thirty-nine samples were positive by culture in Löwenstein-Jensen, and 42 using the MB/BacT system. Positive cultures in the MB/BacT system were verified by acid-fast bacilli staining and PCR. Mycobacterial identification in the MB/BacT took 8 to 46 days (mean 16 days), while the Löwenstein-Jensen culture ranged between 21 and 63 days (mean 35 days). These results show that the MB/BacT semiautomated system is reliable and faster than the manual culture method and can be used as an alternative for the primary identification of Mycobacterium tuberculosis. The PCR assay allows the fast and exact identification of Mycobacterium tuberculosis directly from positive liquid medium.

In Silico Identification of Highly Conserved Epitopes of Influenza A H1N1, H2N2, H3N2, and H5N1 with Diagnostic and Vaccination Potential.

The unpredictable, evolutionary nature of the influenza A virus (IAV) is the primary problem when generating a vaccine and when designing diagnostic strategies; thus, it is necessary to determine the constant regions in viral proteins. In this study, we completed an in silico analysis of the reported epitopes of the 4 IAV proteins that are antigenically most significant (HA, NA, NP, and M2) in the 3 strains with the greatest world circulation in the last century (H1N1, H2N2, and H3N2) and in one of the main aviary subtypes responsible for zoonosis (H5N1). For this purpose, the HMMER program was used to align 3,016 epitopes reported in the Immune Epitope Database and Analysis Resource (IEDB) and distributed in 34,294 stored sequences in the Pfam database. Eighteen epitopes were identified: 8 in HA, 5 in NA, 3 in NP, and 2 in M2. These epitopes have remained constant since they were first identified (~91 years) and are present in strains that have circulated on 5 continents. These sites could be targets for vaccination design strategies based on epitopes and/or as markers in the implementation of diagnostic techniques.

Production of IL-10, TNF and IL-12 by peripheral blood mononuclear cells in Mexican workers exposed to a mixture of benzene-toluene-xylene.

BACKGROUND AND AIMS: Occupational exposure to low-level benzene and the joint action of toluene-xylene probably cause effects on circulating monocytes immune response. We undertook this study to determine relationship between occupational exposure to benzene-toluene-xylene mixture (BTX) and IL-10, TNF and IL-12 production by peripheral blood mononuclear cells. METHODS: Exposure was estimated in 54 workers from a paint company in Mexico City through BTX accumulated potential dose (BTX-APD). Two exposure groups were formed: high and low BTX-APD established with a cutoff point at ≥1.0 of BTX-APD, as a function of the geometric mean of the estimator's value distribution and the higher agreement between BTX-APD ≥1.0 and the areas referred as using (or not) organic solvents in the work process. IL-10, TNF and IL-12 concentrations were measured with ELISA. Through multiple linear regression models, the production of each of the proposed cytokines and of the whole set was assessed. RESULTS: Workers with high BTX-APD showed a significant reduction in TNF production (ß = -1,196.0 pg/mL; p = 0.01); a reduction for IL-10 (ß = -520.3; p = 0.13) and IL-12 (ß = -843.3; p = 0.09) was also observed, although without statistical significance. CONCLUSIONS: TNF production assessed in workers with a high BTX-APD is lower than in those with a low BTX-APD, but not in IL-10 and IL-12 production.