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Background: In recent years, the role of neurotrophins and their receptors in peripheral tissues has been of great interest. At a metabolic level, the brain-derived neurotrophic factor (BDNF) and its receptor trkB have been reported to participate in insulin secretion from the pancreas in response to increases in circulating blood glucose. Objetive: To determines the role of the BDNF-trkB pathway in insulin secretion and pancreatic morphology in rats fed a cafeteria-style diet for 16 weeks. Methods: For the study, male rats of the Wistar strain were divided into three groups as follows: (1) control group (standard diet), (2) CAF group (cafeteria-style diet) and (3) CAF group treated with ANA-12 (TrkB receptor antagonist). After 4 months of intervention, the glucose and insulin tolerance curves, serum insulin levels, body fat and hematoxylin-eosin staining pancreas were evaluated. Results: The results showed that the cafeteria-style diet induced an increase in the amount of body fat, alterations in the glucose tolerance curve, increased insulin circulation levels, increased HOMA indices and increased pancreatic islet size. The antagonism of the trkB receptor in the rats fed a cafeteria-style diet enhanced some effects such as the accumulation of body fat and insulin secretion and induced a greater increase in the pancreas islet size. Conclusions: Under conditions of cafeteria-style diet-induced obesity, the antagonism of the BDNF-trkB pathway had no enhanced effect on the increase in insulin secretion or pancreatic islet size.

Backgrounds and aims – The genus Hechtia (sensu lato) is distributed from the southern United States to northern Central America and includes 95 species. Recent botanical explorations, carried out in the Colima and Jalisco states in search of H. reticulata, led to the discovery of two new species. The aims of this work were to complete the morphological description of H. reticulata and describe these two new species. Material and methods – This study was based on fieldwork and on the revision of literature, protologues, type material, and herbarium specimens. The specimens collected were prepared for storage in the herbarium, analysed, measured, and descriptions were made; measurements were taken from dried specimens. Due to their morphological similarities and the closeness of their populations, the proposed species are compared with H. reticulata. Key results – We propose two new species of Hechtia for Mexico (H. costalegrensis and H. pacifica); an epitype and a complete description of H. reticulata are also provided. The diagnostic characters and morphological affinities of the new species are discussed, including complete morphological descriptions and images; a comparative table is presented, showing the morphological differences between the new species and H. reticulata. A distribution map of the taxa described here and of H. reticulata is included, as well as an identification key and a list of examined specimens of all Hechtia species known to date from Colima and Jalisco.

Background and Objectives: Non-viral bloodborne diseases are a group of infections that are a public health problem worldwide. The incidence of diseases such as brucellosis and syphilis is increasing in the Americas and Europe. Chagas disease is an endemic problem in Latin America, the United States and Europe. This study aims to determine the prevalence of non-viral bloodborne diseases in blood donors and to discuss some issues related to federal regulations for the control and prevention of these infectious diseases in Mexico. Material and methods: A cross-sectional study was conducted in the Western National Medical Center Blood Bank, including 228,328 blood donors (2018–2023). Frequencies, percentages, means, standard deviation and confidence intervals (CI) were calculated for demographic data. Prevalences were expressed as rates per 100,000 with 95% CI. Results: Of 3949 seroreactive or undetermined blood donors at the first screening, a total of 682 (0.299%) completed their follow-up test and were positive for Treponema pallidum (478), Trypanosoma cruzi (83), or Brucella spp. (121). The overall prevalence for non-viral bloodborne diseases was 299 per 100,000 blood donors. The prevalence for syphilis, Chagas disease, and Brucella was 209, 36, and 53 per 100,000 respectively. Conclusion: Federal regulations should be reviewed to formulate specific public health policies focused on controlling and preventing nonviral bloodborne diseases.

Abstract The zoonotic Rift Valley fever virus (RVFV) can cause severe disease in humans and has pandemic potential, yet no approved vaccine or therapy exists. Here we describe a dual-mechanism human monoclonal antibody (mAb) combination against RVFV that is effective at minimal doses in a lethal mouse model of infection. We structurally analyze and characterize the binding mode of a prototypical potent Gn domain-A-binding antibody that blocks attachment and of an antibody that inhibits infection by abrogating the fusion process as previously determined. Surprisingly, the Gn domain-A antibody does not directly block RVFV Gn interaction with the host receptor low density lipoprotein receptor-related protein 1 (LRP1) as determined by a competitive assay. This study identifies a rationally designed combination of human mAbs deserving of future investigation for use in humans against RVFV infection. Using a two-pronged mechanistic approach, we demonstrate the potent efficacy of a rationally designed combination mAb therapeutic.

Abstract Substantial increases in the conjugation of the main human SUMO paralogs, SUMO1, SUMO2, and SUMO3, are observed upon exposure to different cellular stressors, and such increases are considered important to facilitate cell survival to stress. Despite their critical cellular role, little is known about how the levels of the SUMO modifiers are regulated in the cell, particularly as it relates to the changes observed upon stress. Here we characterize the contribution of alternative splicing towards regulating the expression of the main human SUMO paralogs under normalcy and three different stress conditions, heat-shock, cold-shock, and Influenza A Virus infection. Our data reveal that the normally spliced transcript variants are the predominant mature mRNAs produced from the SUMO genes and that the transcript coding for SUMO2 is by far the most abundant of all. We also provide evidence that alternatively spliced transcripts coding for protein isoforms of the prototypical SUMO proteins, which we refer to as the SUMO alphas, are also produced, and that their abundance and nuclear export are affected by stress in a stress- and cell-specific manner. Additionally, we provide evidence that the SUMO alphas are actively synthesized in the cell as their coding mRNAs are found associated with translating ribosomes. Finally, we provide evidence that the SUMO alphas are functionally different from their prototypical counterparts, with SUMO1α and SUMO2α being non-conjugatable to protein targets, SUMO3α being conjugatable but targeting a seemingly different subset of protein from those targeted by SUMO3, and all three SUMO alphas displaying different cellular distributions from those of the prototypical SUMOs. Thus, alternative splicing appears to be an important contributor to the regulation of the expression of the SUMO proteins and the cellular functions of the SUMOylation system.

Neutrophil extracellular trap formation (NETosis) is a mechanism used by neutrophils to capture pathogens with their own DNA. However, the exacerbation of this immune response is related to serious inflammatory diseases. Aging is known to lead to an excessive increase in NETosis associated with various diseases. Under this scenario, the search for strategies that regulate the release of NETosis in older people becomes relevant. High-intensity interval training (HIIT) involves repeated bouts of relatively intense exercise with alternating short recovery periods. This training has shown beneficial effects on health parameters during aging and disease. However, little is known about the potential role of HIIT in the regulation of NETosis in healthy older people. The aim of this study was to evaluate the induction of NETosis by serum from healthy young and older men, before and after 12 weeks of HIIT using healthy neutrophils as a biosensor. HIIT was performed 3 times per week for 12 weeks in young (YOUNG; 21 ± 1 years, BMI 26.01 ± 2.64 kg⋅m−2, n = 10) and older men (OLDER; 66 ± 5 years, BMI 27.43 ± 3.11 kg⋅m−2, n = 10). Serum samples were taken before and after the HIIT program and NETosis was measured with live cell imaging in donated neutrophils cultured with serum from the participants for 30 h. Our results showed that serum from older men at baseline induced greater baseline NETosis than younger men (p

Plant breeding is used to develop crops with host resistance to aphids, however, virulent biotypes often develop that overcome host resistance genes. We tested whether the symbionts, Arsenophonus (A) and Wolbachia (W), affect virulence and fecundity in soybean aphid biotypes Bt1 and Bt3 cultured on whole plants and detached leaves of three resistant, Rag1, Rag2 and Rag1 + 2, and one susceptible, W82, soybean genotypes. Whole plants and individual aphid experiments of A. glycines with and without Arsenophonus and Wolbachia did not show differences in overall fecundity. Differences were observed in peak fecundity, first day of deposition, and day of maximum nymph deposition of individual aphids on detached leaves. Bt3 had higher fecundity than Bt1 on detached leaves of all plant genotypes regardless of bacterial profile. Symbionts did not affect peak fecundity of Bt1 but increased it in Bt3 (A+W+) and all Bt3 strains began to deposit nymphs earlier than the Bt1 (A+W−). Arsenophonus in Bt1 delayed the first day of nymph deposition in comparison to aposymbiotic Bt1 except when reared on Rag1 + 2. For the Bt1 and Bt3 strains, symbionts did not result in a significant difference in the day they deposited the maximum number of nymphs nor was there a difference in survival or variability in number of nymphs deposited. Variability of number of aphids deposited was higher in aphids feeding on resistant plant genotypes. The impact of Arsenophonus on soybean aphid patterns of fecundity was dependent on the aphid biotype and plant genotype. Wolbachia alone had no detectable impact but may have contributed to the increased fecundity of Bt3 (A+W+). An individual based model, using data from the detached leaves experiment and with intraspecific competition removed, found patterns similar to those observed in the greenhouse and growth chamber experiments including a significant interaction between soybean genotype and aphid strain. Combining individual data with the individual based model of population growth isolated the impact of fecundity and host resistance from intraspecific competition and host health. Changes to patterns of fecundity, influenced by the composition and concentration of symbionts, may contribute to competitive interactions among aphid genotypes and influence selection on virulent aphid populations.

Summary: Background: What baseline predictors would be involved in mortality in people with primary Sjögren syndrome (SjS) remains uncertain. This study aimed to investigate the baseline characteristics collected at the time of diagnosis of SjS associated with mortality and to identify mortality risk factors for all-cause death and deaths related to systemic SjS activity measured by the ESSDAI score. Methods: In this international, real-world, retrospective, cohort study, we retrospectively collected data from 27 countries on mortality and causes of death from the Big Data Sjögren Registry. Inclusion criteria consisted of fulfilling 2002/2016 SjS classification criteria, and exclusion criteria included chronic HCV/HIV infections and associated systemic autoimmune diseases. A statistical approach based on a directed acyclic graph was used, with all-cause and Sjögren-related mortality as primary endpoints. The key determinants that defined the disease phenotype at diagnosis (glandular, systemic, and immunological) were analysed as independent variables. Findings: Between January 1st, 2014 and December 31, 2023, data from 11,372 patients with primary SjS (93.5% women, 78.4% classified as White, mean age at diagnosis of 51.1 years) included in the Registry were analysed. 876 (7.7%) deaths were recorded after a mean follow-up of 8.6 years (SD 7.12). Univariate analysis of prognostic factors for all-cause death identified eight Sjögren-related variables (ocular and oral tests, salivary biopsy, ESSDAI, ANA, anti-Ro, anti-La, and cryoglobulins). The multivariate CPH model adjusted for these variables and the epidemiological features showed that DAS-ESSDAI (high vs no high: HR = 1.68; 95% CI, 1.27–2.22) and cryoglobulins (positive vs negative: HR = 1.72; 95% CI, 1.22–2.42) were independent predictors of all-cause death. Of the 640 deaths with available information detailing the specific cause of death, 14% were due to systemic SjS. Univariate analysis of prognostic factors for Sjögren-cause death identified five Sjögren-related variables (oral tests, clinESSDAI, DAS-ESSDAI, ANA, and cryoglobulins). The multivariate competing risks CPH model adjusted for these variables and the epidemiological features showed that oral tests (abnormal vs normal results: HR = 1.38; 95% CI, 1.01–1.87), DAS-ESSDAI (high vs no high: HR = 1.55; 95% CI, 1.22–1.96) and cryoglobulins (positive vs negative: HR = 1.52; 95% CI, 1.16–2) were independent predictors of SjS-related death. Interpretation: The key mortality risk factors at the time of SjS diagnosis were positive cryoglobulins and a high systemic activity scored using the ESSDAI, conferring a 2-times increased risk of all-cause and SjS-related death. ESSDAI measurement and cryoglobulin testing should be considered mandatory when an individual is diagnosed with SjS. Funding: Novartis.

Pitcairnia abscondita sp. nov., known until now only from the Municipalities of Cabo Corrientes, Mascota, Puerto Vallarta, San Sebastián del Oeste and Talpa de Allende in the State of Jalisco, Mexico, is here described and illustrated. The new taxon was confused with P. imbricata for long time, but differs from this species by its green floral bracts with the apex divergent to spreading (vs. red and appressed) and by the appendiculate at the base chartreuse-green petals (vs. not appendiculate yellow petals). Images and a distribution map of the taxa are presented.

Background: Bromeliaceae are widespread in Mexico and present in all types of vegetation. A high number of species are restricted to the country. Jalisco is the fifth Mexican state regarding Bromeliaceae richness and 18 % of its species are state endemics. Questions and / or Hypotheses: How bromeliads are distributed in Western Sierra-Coast region of Jalisco? What is the endemism status of bromeliads in the region? Studied species: Native Bromeliaceae of WSC. Study site and dates: WSC region in Jalisco, collections from 1926 to 2020. Methods: Data were obtained by herbarium material revision and field expeditions. We analyzed life form, distribution by vegetation type, altitudinal range, and recollection activity per year. A richness map was generated. To determine the affinity of the bromeliad flora with other regions of the state, a cluster analysis was performed using UPGMA method. Results: We found nine genera and 53 species, richest genera were Tillandsia and Pitcairnia. Epiphyte was the commonest life form. Oak forest had the highest species number, most taxa were found between 250-750 m asl. Most collections come from the municipality of Cabo Corrientes accounting for 66 % of total species in WSC. The study area hosts, six species of endemic bromeliads. Conclusions: Despite to their restricted distribution, none of the endemic species from WSC are listed under special protection. The WSC should be considered for conservation. The tourism development, deforestation and climate change could have a negative impact on bromeliads, especially epiphytes that depend entirely on the host trees.

AbstractNon-mammalian model organisms have been essential for our understanding of the mechanisms that control development, disease, and physiology, but they are underutilized in pharmacological and toxicological phenotypic screening assays due to their low throughput in comparison with cell-based screens. To increase the utility of using Drosophila melanogaster

Background and AimsEpiphytes are an important component of tropical forests, also they are sensitive to disturbance and deforestation caused by humans, since they depend on their host trees and the micro environmental conditions that these provide. The aim of this study was to analyze the differences in species richness, composition, and vertical distribution of epiphytic angiosperms between areas with natural and disturbed forest at the Northern Coast of Jalisco state, Mexico.MethodsThe presence/absence of epiphytic angiosperms was evaluated in each vertical zone of a selected tree, as well as those present in the understory, both in natural and disturbed sites in three types of vegetation (gallery forest, oak forest, tropical semideciduous forest) with a total of 30 plots of 20 m × 20 m in six sites. Alpha diversity was calculated for each site, as well as species turnover (beta diversity) between habitats. An analysis of variance was performed to determine if there was a significant difference in species richness between sites and, also to compare the height and diameter at breast height (DBH) of the host trees. Multivariate analyzes were used to group the sites according to their floristic composition. Furthermore, a linear regression was performed to detect any relationship between the number of species and the phorophyte structure.ResultsWe recorded 45 species, 29 genera and nine families of epiphytic angiosperms. The most diverse families were Bromeliaceae and Orchidaceae and the richest genus was Tillandsia. Although the disturbed sites had more species, a significant difference in richness was not found, except for the disturbed gallery forest. Epiphytic angiosperms presented a high beta diversity, since the sites shared only between 2 and 18% of the recorded species. The inner portion of the canopy (Z3 and Z4) hosted most of the species in all sites and the understory had a high representation of epiphytes except for the disturbed oak forest, where these were absent. A relationship between the DBH and the number of species was found only at the disturbed sites, however, it was highly influenced by the high number of taxa registered in disturbed gallery forest. Therefore, the size of the trees could not be considered a factor in determining the diversity of epiphyte species.ConclusionThe diversity of epiphytic angiosperm species from the North Coast of Jalisco has not been severely affected by the human disturbance. Most of the species have morphological and physiological adaptations that allow their establishment and survival in adverse climatic conditions. Our results suggest that epiphytic angiosperms cannot be considered as a good indicator for natural or disturbed environments in this region but should be considered in environmental conservation, as they present a high beta diversity.

BackgroundLatino communities are among the most heavily impacted populations by the COVID-19 pandemic in the United States due to intersectional barriers to care. Crowdsourcing open contests can be an effective means of community engagement but have not been well studied in Latino populations nor in addressing the COVID-19 pandemic. ObjectiveThe aims of this study are to (1) implement and evaluate a crowdsourcing open contest to solicit a name for a COVID-19 social marketing campaign for Latino populations in Maryland and (2) conduct a thematic analysis of submitted entries to guide campaign messaging. MethodsTo assess the level of community engagement in this crowdsourcing open contest, we used descriptive statistics to analyze data on entries, votes, and demographic characteristics of participants. The submitted text was analyzed through inductive thematic analysis. ResultsWe received 74 entries within a 2-week period. The top 10 entries were chosen by community judges and the winner was decided by popular vote. We received 383 votes within 1 week. The most common themes were collective efficacy, self-efficacy, and perceived benefits of COVID-19 testing. We used these themes to directly inform our social marketing intervention and found that advertisements based on these themes became the highest performing. ConclusionsCrowdsourcing open contests are an effective means of community engagement and an agile tool for guiding interventions to address COVID-19, including in populations impacted by health care disparities, such as Latino communities. The thematic analysis of contest entries can be a valuable strategy to inform the development of social marketing campaign materials.