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Objectives: To identify the SARS-CoV-2 variants Delta and Omicron during the fourth wave of the COVID-19 pandemic in Mexico using samples taken from 19 locations in 18 out of the 32 states. Methods: The genetic material concentration was done with PEG/NaCl precipitation, SARS-CoV-2 presence was confirmed by reverse transcriptase-quantitative polymerase chain reaction assay, the variant detection was carried out using a commercial mutation detection panel kit, and variant/mutation confirmation was done by amplicon sequencing of receptor-binding domain target region. The study used 41 samples. Results: The Delta variant was confirmed in two samples during August 2021 (Querétaro and CDMX) and in three samples during November 2021 (Aguascalientes, Ciudad Juárez campuses, and Nuevo Leon). In December 2021, another sample with the Delta variant was confirmed in Nuevo Leon. Between January to March 2022 only the presence of Omicron was confirmed, (variant BA.1). Additionally, in this period six samples were identified with the status "Variant Not Determined". Conclusion: To our knowledge, this study is one of the first to identify Omicron and Delta variants with polymerase chain reaction in Mexico and Latin America and its distribution across the country with 56% Mexican states making it a viable alternative for variant detection without conducting a large quantity of sequencing of clinical tests.

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Background: Haiti's hypertension prevalence among adults ≥40 years of age is nearly twice that of nations in the Americas. Haiti Health Initiative (HHI) developed a hypertension management protocol for use in outreach clinics in Timo, a rural mountainous community in Haiti. This study aimed to evaluate the effectiveness of the hypertension protocol for treating adults ≥40 years of age and pregnant women with severe hypertension. Methods: This retrospective longitudinal study included 209 patients across 1148 clinic visits/encounters. De-identified medical records from 11 biannual outreach clinics between April 2014 to April 2019 were reviewed for analysis. Descriptive statistics, paired t-tests, and multilevel models were performed. The primary outcome was systolic and diastolic blood pressure measurements at each clinic visit. Findings: In the study (n = 1148 visits), hypertension and severe hypertension prevalence were respectively 79·8% and 38·4%. Multilevel models showed a decrease of 0·29 mmHg (p = 0·37) in systolic blood pressure and a decrease in diastolic blood pressure of 0·66 mmHg (p < 0·001) per visit. Individual factors and protocol adherence did not predict a reduction in blood pressure. Conclusion: Effective management of hypertension and other chronic conditions among hard-to-reach populations with limited healthcare access requires comprehensive outreach efforts that address care antecedents, structures, and processes. Although outreach clinics made treatment accessible to vulnerable populations, the protocol, which used medications with previously demonstrated efficacy, had little impact on reducing blood pressure in patients with severe hypertension.

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Animals frequently evolve unique suites of traits on islands, but whether plants evolve comparable island syndromes remains unresolved. Here, we test the prediction on the basis of natural history observations that insect-pollinated plants evolve smaller flowers on islands than on mainland communities. We examined 556 plant species representing 136 phylogenetically independent contrasts between island and mainland sister taxa. We focused on endemic taxa originating from the Americas associated with seven tropical and subtropical islands of the Pacific Ocean. Contrary to conventional wisdom, flowers were not on average smaller on islands than on the mainland. On specific archipelagos (the Galápagos Islands and Revillagigedo Islands), however, island taxa did evolve smaller flowers. Divergence in flower size between island and mainland taxa also varied among taxonomic families, such that some plant families evolved smaller flowers on islands, other families evolved larger flowers on islands, and some families exhibited no divergence in flower size between island and mainland taxa. Overall, our results show that there is no general island syndrome for flower size, but instead that the evolution of floral morphology is complex and context dependent, depending on variation among islands and plant families. Our results also suggest that if island floras are typically dominated by small flowered species, as suggested by natural history observations, then ecological filtering is a more likely explanation of this pattern than evolutionary divergence postcolonization. We propose future studies that could disentangle the relative roles of ecological filtering and evolution in the distribution of floral traits on islands.

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Plant defenses against herbivores are predicted to evolve to be greater in warmer climates, such as lower latitudes where herbivore pressure is also thought to be higher. Instead, recent findings are often inconsistent with this expectation, suggesting alternative hypotheses are needed. We tested for latitudinal gradients in plant defense evolution at the macroevolutionary scale by characterizing plant chemical defenses across 80 species of the evening primroses, spanning both North and South America. We quantified phenolics in leaves, flowers, and fruits, using advanced analytical chemistry techniques. Dominant individual ellagitannin compounds, total concentrations of ellagitannins, flavonoids, total phenolics, and compound diversity were quantified. Variation in these compounds was predicted with latitude, temperature, precipitation, and continent using phylogenetic generalized least squares (PGLS) multiple regression models. Latitude did not strongly explain variation in chemical defenses. Instead, fruit total ellagitannins, oenothein A, and total phenolics were greater in species inhabiting regions with colder climates. Using analytical chemistry and 80 species in two continents, we show that contrary to classic predictions, concentrations of secondary metabolites are not greater at lower latitudes or in warmer regions. We propose higher herbivore pressure in colder climates and gradients in resource availability as potential drivers of the observed patterns in Oenothera.

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