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Objective: To estimate the effectiveness of several vaccine brands-Pfizer, Astra, and Sinovac-against symptomatic COVID-19 without information on vaccination at the individual level., Methods: We use data of mass vaccination programs-specifically, for sexagenarians and quinquagenarians-in three large municipalities of Mexico (Monterrey, Guadalupe, and San Nicolás) to conduct a two-step time series estimation procedure involving a synthetic control group. The data covers the period between the first week of March 2020 and the first week of October 2021., Results: Vaccine effectiveness is a concave function of time. At the peak, Pfizer reaches 92.6 % effectiveness, Astra 83.6 % and Sinovac 65.6 %. This occurs 9 to 12 weeks after the first shot., Conclusion: The results indicate that the three vaccines protect against symptomatic COVID-19. Nevertheless, they offer different levels of protection. The results also suggest that VE-under a two-shot scheme-reaches its peak 9 to 16 weeks after the first shot. Moreover, there seems to be a trade-off between achieving higher efficiency by administering the 2nd shot earlier or extending the protection period by administering it later., 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 Elsevier Ltd. All rights reserved.)

Background: The global inequity in the distribution of COVID-19 vaccines underscores the urgent need for innovative and cost-effective vaccine technologies to address access disparities and implement local manufacturing capabilities. This is essential for achieving and sustaining widespread immunity, and for ensuring timely protection of vulnerable populations during future booster campaigns in lower- middle income countries (LMICs)., Methods: To address this need, we conducted a phase II clinical trial to evaluate the safety and immunogenicity of the locally manufactured AVX/COVID-12 "Patria" (AVX) vaccine as a booster dose. The vaccine was administered either intramuscularly (IM) or intranasally (IN) to participants who had previously completed a vaccination regimen for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using adenoviral vector, inactivated virus, or mRNA-based vaccines. Participants with initial anti-spike IgG titers below 1,200 U/mL were included, allowing us to observe the booster effect induced by vaccination., Results: Both IM and IN immunization with AVX were found to be safe and well-tolerated. The vaccine induced a significant (>2.5-fold) increase in neutralizing antibodies against the ancestral Wuhan strain and variants of concern (VOCs), including Alpha, Beta, Delta, and Omicron (BA.2 and BA.5). This immune response was further supported by increased cellular production of interferon-gamma (IFN-γ), demonstrating a robust and multifaceted immune reaction., Conclusions: The administration of AVX as a booster dose, whether through IM or IN routes, was safe and well-tolerated. The vaccine extended immune responses not only against the ancestral Wuhan-1 strain but also against various VOCs. Its ability to enhance preexisting immune responses suggests a potential contribution to expanding and sustaining herd immunity within the population., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Laboratorios Avimex S.A. de C.V. reports financial support was provided by Consejo Nacional de Humanidades, Ciencia y Tecnología. México. Bernardo Lozano-Dubernard reports financial support was provided by Laboratorios Avimex S.A. de C.V. P.P., F.K., and A.G.-S. has patent #62/994,252 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/018,457 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/020,503 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/024,436 pending to Mount Sinai. P.P., F.K., and A.G.-S. has patent #63/251,020 pending to Mount Sinai. M.T., D.S.-M., C.L.-M., H.E.C.-C., F.C.-P., G.P.D.L., and B.L.-D. has patent #PCT/IB2022/058886. MX/a/2021/011439 pending to Avimex S.A. de C.V. The vaccine candidate administered in this study was developed by faculty members at the Icahn School of Medicine at Mount Sinai including P.P., F.K., and A.G.-S. Mount Sinai is seeking to commercialize this vaccine; therefore, the institution and its faculty inventors could benefit financially. The Icahn School of Medicine at Mount Sinai has filed patent applications relating to SARS-849 CoV-2 serological assays (USA Provisional Application Numbers: 62/994,252, 63/018,457, 63/020,503, and 63/024,436) and NDV-based SARS-CoV-2 vaccines (USA Provisional Application Number: 63/251,020) which list F.K. as co-inventor. A.G.-S. and P.P. are co-inventors in the NDV-based SARS-CoV-2 vaccine patent application. Patent applications were submitted by the Icahn School of Medicine at Mount Sinai. Mount Sinai has spun out a company, Kantaro, to market serological tests for SARS-CoV-2 and another company, CastleVax, to commercialize SARS-CoV-2 vaccines. F.K., P.P., and A.G.-S. serve on the scientific advisory board of CastleVax and are listed as co-founders of the company. F.K. has consulted for Merck, Seqirus, Curevac, and Pfizer, and is currently consulting for Gritstone, Third Rock Ventures, GSK, and Avimex. The F.K. laboratory has been collaborating with Pfizer on animal models of SARS-CoV-2. C.L.-M. has consulted for AstraZeneca. The A.G.-S. laboratory has received research support from GSK, Pfizer, Senhwa Biosciences, Kenall Manufacturing, Blade Therapeutics, Avimex, Johnson & Johnson, Dynavax, 7Hills Pharma, Pharmamar, ImmunityBio, Accurius, Nanocomposix, Hexamer, N-fold LLC, Model Medicines, Atea Pharma, Applied Biological Laboratories, and Merck. A.G.-S. has consulting agreements for the following companies involving cash and/or stock: Amovir, Vivaldi Biosciences, Contrafect, 7Hills Pharma, Avimex, Pagoda, Accurius, Esperovax, Farmak, Applied Biological Laboratories, Pharmamar, CureLab Oncology, CureLab Veterinary, Synairgen, Paratus, Pfizer, and Prosetta. A.G.-S. has been an invited speaker in meeting events organized by Seqirus, Janssen, Abbott, and AstraZeneca. PP has a consulting agreement with Avimex. Members of Avimex developed the live vaccine used in this study. Avimex filed patent applications with Mount Sinai and CONAHCYT. M.T., D.S.-M., C.L.-M., H.E.C.-C., F.C.-P., G.P.D.L., and B.L.-D. are named as inventors on at least one of those patent applications. The clinical study was entirely performed in Mexico, and Mount Sinai had no role in it. The rest of the participants are employees of their corresponding institutions and declare no competing interests. If there are other authors, they 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 Ltd.. All rights reserved.)

This research addresses the impact of illicit drug use on labour market outcomes of men in Mexico. We leverage statistical information from three waves of a comparable national survey and make use of the Lewbel's heteroskedasticity-based instrumental variable strategy to deal with the endogeneity of the drug consumption. Our results suggests that drug consumption has fairly negative effects in the Mexican context: it reduces employment, occupational attainment and formality and raises unemployment of local males. These effects seem larger than those estimated for high-income economies., 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.)

Background: As the migratory flow to the USA has intensified in recent months, health problems associated have been identified. The aim of this work was the identification of malaria cases imported into Mexican territory., Methods: Operational definitions of suspected and confirmed cases were used for investigation of malaria cases. Detection of parasitic entities by thick blood smear and molecular biology served as a confirmatory test. With the characteristics of the cases, a heat map was made to determine common clinical pictures. Finally, epidemiological analysis of cases was performed for the construction of timelines of imported malaria and the tracing of migratory routes., Results: Twelve migrants from four countries were treated for presenting clinical symptoms with suspected dengue or malaria. Malaria was confirmed and two Plasmodium species were identified. From the epidemiological dates of arrival in Mexico, onset of symptoms and migratory routes, we speculate that ten cases acquired P. vivax during their crossing through Honduras, El Salvador or Guatemala. For the Guinea cases, we conclude that there was African importation of P. falciparum., Conclusion: The epidemiological panorama of malaria cases imported into Mexico show the need to join efforts to ensure universal access to health services, with the objective of timely detection of imported cases., 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 Ltd.. All rights reserved.)

Introduction: Prenatal and early-life exposure to air pollution and extreme temperatures are associated with childhood asthma and wheeze. However, potential windows of susceptibility and their sex-specific and interactive effects have not been fully elucidated. We aimed to identify critical windows of susceptibility and evaluate sex-specific effects in these associations, and evaluate exposure interactions., Methods: We analyzed data from 468 mother-child pairs enrolled in the PROGRESS birth cohort in Mexico City. Daily residential levels of PM 2.5 , NO 2 , and temperature were generated from our validated spatiotemporally resolved models from conception to age 4 years. Childhood asthma and wheeze outcomes were collected at 4-6 and 7-8 years. Distributed lag nonlinear models (DLNMs) were used to identify susceptible windows for prenatal weekly-specific and postnatal monthly-specific associations of air pollution and temperature with respiratory outcomes adjusting for covariates. To evaluate sex-specific effects, DLNMs were stratified. Joint effects were assessed using relative excess risk due to interaction and attributable proportion., Results: Mid-gestation was a critical window for both PM 2.5 (weeks 20-28, cumulative OR: 1.18 [95% CI: 1.01, 1.37]; weeks 19-26, cumulative OR: 1.18 [95% CI: 1.02, 1.36]) and NO 2 (weeks 18-25, cumulative OR: 1.16 [95% CI: 1.02, 1.31]) exposure, associated with higher odds of wheeze. Postnatal exposure to PM 2.5 and NO 2 during the first year of life was also linked to higher odds of wheeze. The warmer and colder temperatures showed mixed effects on respiratory outcomes. We observed a synergistic interaction between high PM 2.5 and high temperature exposure during the first year of life, associated with higher odds of current wheeze. The associations of prenatal air pollution and temperature exposure with respiratory outcomes were more pronounced in males., Conclusions: Early-life air pollution exposure contributes to the development of childhood asthma and wheeze, while exposure to temperature showed mixed associations with respiratory outcomes., 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 Author(s). Published by Elsevier Ltd.. All rights reserved.)

Introduction: This study assessed quit attempts among adults who use cigarettes either exclusively or with e-cigarettes in Mexico, where non-daily smoking predominates., Methods: An open cohort of Mexican adults who smoke was surveyed every four months from November 2018 to March 2021. Participants followed to the next survey were analyzed (n = 2220 individuals, 4560 observations). Multinomial logistic models regressed smoking quit attempts reported at the followup survey (ref = no attempt; tried to quit; sustained attempt of ≥30 days) on e-cigarette use frequency (none = ref; 1-2 days/week; ≥3 days/week), adjusting for sociodemographics and smoking-related variables. Additional models subdivided e-cigarette users by intentions to quit smoking in the next six months (i.e., yes/no), use of nicotine (i.e., yes/no), and vaping device used (i.e., open/closed)., Results: At 4-month follow-up, 32.7 % had tried to quit, and 2.9 % had quit for 30 days or more. Compared to those who smoke exclusively, occasional, and frequent e-cigarette users were more likely to try to quit (Adjusted Relative Risk Ratio or ARRR = 1.26 and 1.66, respectively) but no more likely to sustain their quit attempt. Among those who intended to quit smoking, e-cigarette users were no more likely to either try or sustain quit attempts. Furthermore, use of e-cigarettes with nicotine (59.6 %) was unassociated with cessation except that those who frequently used e-cigarettes with nicotine were more likely to try to quit than those who smoke exclusively (ARRR = 1.88). Device type used was not differentially associated with outcomes., Conclusions: Mexicans who smoke and use e-cigarettes appear more likely than those who smoke exclusively to try to quit but not to sustain abstinence., 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. Published by Elsevier Ltd.)

In this study, we report the innovative application of whole-cell patch-clamp electrophysiology in assessing broad-spectrum neutralisation by three different antivenoms, of venoms from the medically significant scorpion genus Centruroides. Envenomations by as many as 21 species from the Centruroides genus result in up to 300,000 envenomations per year in Mexico, which poses significant and potentially life-threatening pathophysiology. We first evaluated the in vitro manifestation of envenomation against two human voltage-gated sodium (hNa V ) channel subtypes: hNa V 1.4 and hNa V 1.5, which are primarily expressed in skeletal muscles and cardiomyocytes, respectively. The neutralisation of venom activity was then characterised for three different antivenoms using a direct competition model against the more potent target, hNa V 1.4. While broad-spectrum neutralisation was identified, variation in neutralisation arose for Centruroides elegans, C. limpidus, C. noxius and C. suffusus venoms, despite the presence of a number of these venoms within the immunising mixture. This raises questions regarding the truly "broad" neutralisation capacity of the antivenoms. This study not only extends previous validation of the in vitro investigation of antivenom efficacy utilising the whole-cell patch-clamp technique but also underscores the potential of this animal-free model in exploring cross-reactivity, experimental scalability, and most importantly, informing clinical management practices regarding the administration of antivenom in Mexico., 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 Inc. All rights reserved.)

The inflorescences of the Mexican gordolobo are used as a folk medicine to treat various respiratory diseases. Currently, the botanical species that bear the name Mexican gordolobo belong to the genera Gnaphalium and Pseudognaphalium. Despite a long history of traditional use, most Mexican gordolobo species have never been fully chemically characterized, and the range of constituents in the species has not been comprehensively reported. To establish a quality control and chemical characterization method, a total of 49 samples belonging to 18 species of Pseudognaphalium and four species of Gnaphalium were studied. Nine flavones were quantified using a UPLC-PDA method. The method was validated in terms of linearity (R 2 > 0.99), precision (intra- and inter-day: 0.1-3.9%), accuracy (96-103%), detection limit (10 ng/mL), limit of quantification (25 ng/mL) and robustness. 3-Methylquercetin, luteolin, quercetin, 3,5-dihydroxy-6,7,8-trimethoxyflavone, apigenin and gnaphaliin A were present at relatively high levels in most of the samples analyzed. The samples of P. oxyphyllum and P. liebmannii showed the highest content of the 9 compounds analyzed. Whereas the samples of the 5 species of Gnaphalium showed the lowest levels, including non-detectable, of the 9 compounds quantified. This marks an important difference with Pseudognaphalium species. Furthermore, using UHPLC-ESI-QToF data with targeted and non-targeted approaches, 57 compounds, were identified in Mexican gordolobo samples. Flavonoids were the main group of compounds found in Mexican gordolobo., 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.)

Trypanosoma cruzi is the parasite responsible for Chagas disease. The parasite has been classified into six taxonomic assemblages: TcI-TcVI and TcBat (aka Discrete Typing Units or Near-Clades). No studies have focused on describing the genetic diversity of T. cruzi in the northwestern region of Mexico. Within the Baja California peninsula lives Dipetalogaster maxima, the largest vector species for CD. The study aimed to describe the genetic diversity of T. cruzi within D. maxima. A total of three Discrete Typing Units (DTUs) were found (TcI, TcIV, and TcIV-USA). TcI was the predominant DTU found (∼75% of samples), in concordance with studies from the southern USA, one sample was described as TcIV while the other ∼20% pertained to TcIV-USA, which has recently been proposed to have enough genetic divergence from TcIV, to merit its own DTU. Potential phenotype differences between TcIV and TcIV-USA should be assessed in future studies., 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 © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background and Aim: An association between lead (Pb) exposure and antisocial behaviors has been documented, but findings have been inconclusive. We aimed to estimate the association between prenatal, early childhood, and preadolescent/adolescent (periadolescent) Pb exposure and aggression and conduct problems in periadolescent residents of Mexico City., Methods: Using information from the ELEMENT cohort study, we assessed prenatal Pb exposure through maternal patella Pb (MPPb) measurement during the puerperium, early childhood (birth to 5 years of age) exposure through a cumulative blood lead index (CBLI), and periadolescent exposure through a blood Pb (BPb) measurement concurrent with the evaluation of the outcomes. Outcomes were assessed during periadolescence using the parent-reported scales of aggression and conduct problems of the Behavioral Assessment System for Children-2nd version (BASC-2). We modeled the association between Pb exposure at each stage and each outcome (defined as a T-score ≥60 in the corresponding behavioral scale) using logistic regression, adjusting for sex, maternal age at delivery, maternal education, and household socioeconomic status (SES). The differential effect by sex was assessed with an interaction term in the models., Results: 743, 704, and 595 participants were respectively eligible for inclusion in final models of prenatal, early childhood, and periadolescent Pb exposure. Median Pb exposure at each stage was 9.9 µg/g for MPPb (prenatal), 5.19 µg/dl for CBLI (early childhood), and 2.62 µg/dl for concurrent BPb (periadolescence). 12 % of participants met the criterion for aggression, and 15 % for conduct problems. In adjusted models, a one interquartile range increase in MPPb increased the odds of conduct problems (OR:1.31; 95 % CI: 1.01, 1.70) and aggression (OR=1.24; 95 % CI: 0.93, 1.65) during periadolescence. Pb exposure during early childhood or periadolescence was not associated with either outcome. We found no evidence of interactions by sex., Conclusions: Exposure to Pb during the prenatal stage was associated with aggression and conduct problems during periadolescence., 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 © 2022 Elsevier B.V. All rights reserved.)

Background: Newborn screening for glucose-6-phosphate dehydrogenase deficiency (G6PDd) was implemented in Mexico beginning in 2017. In a Mexican population, genotyping analysis of G6PD as a second-tier method identified a previously unreported missense variant, p.(Ser184Cys), which we propose to call "Toluca", and the extremely rare p.(Gln195His) or "Tainan" variant, which was previously described in the Taiwanese population as a Class II allele through in silico evaluations. Here, we sought to perform in vitro biochemical characterizations of the Toluca and Tainan G6PD natural variants and describe their associated phenotypes., Methods: The "Toluca" and "Tainan" variants were identified in three unrelated G6PDd newborn males, two of whom lacked evidence of acute hemolytic anemia (AHA) or neonatal hyperbilirubinemia (NHB). We constructed wild-type (WT), Tainan, and Toluca G6PD recombinant enzymes and performed in vitro assessments., Results: Both variants had diminished G6PD expression, decreased affinities for glucose-6-phosphate and NADP + substrates, significant decreases in catalytic efficiency (∼97 % with respect to WT-G6PD), and diminished thermostabilities that were partially rescued by NADP + . In silico protein modeling predicted that the variants would have destabilizing effects on the protein tertiary structure, potentially reducing the enzyme half-lives and/or catalytic efficiencies., Conclusion: Our data suggest that G6PD "Tainan" and "Toluca" are potential Class II natural variants, which agrees with the absence of chronic nonspherocytic hemolytic anemia (CNSHA) in our patients. It remains to be determined whether these variants represent high-risk genetic factors for developing CNSHA, AHA, and/or NHB., 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 © 2022 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)